You are viewing a plain text version of this content. The canonical link for it is here.
Posted to commits@hbase.apache.org by gi...@apache.org on 2018/05/25 14:48:15 UTC
[11/29] hbase-site git commit: Published site at
477f9fdb32873387231c5fbbff130ba8bf7b5d68.
http://git-wip-us.apache.org/repos/asf/hbase-site/blob/621479e1/devapidocs/src-html/org/apache/hadoop/hbase/master/balancer/BaseLoadBalancer.Cluster.MoveRegionAction.html
----------------------------------------------------------------------
diff --git a/devapidocs/src-html/org/apache/hadoop/hbase/master/balancer/BaseLoadBalancer.Cluster.MoveRegionAction.html b/devapidocs/src-html/org/apache/hadoop/hbase/master/balancer/BaseLoadBalancer.Cluster.MoveRegionAction.html
index 7f42212..d4bf03c 100644
--- a/devapidocs/src-html/org/apache/hadoop/hbase/master/balancer/BaseLoadBalancer.Cluster.MoveRegionAction.html
+++ b/devapidocs/src-html/org/apache/hadoop/hbase/master/balancer/BaseLoadBalancer.Cluster.MoveRegionAction.html
@@ -1159,434 +1159,442 @@
<span class="sourceLineNo">1151</span> }<a name="line.1151"></a>
<span class="sourceLineNo">1152</span> }<a name="line.1152"></a>
<span class="sourceLineNo">1153</span><a name="line.1153"></a>
-<span class="sourceLineNo">1154</span> public void setRackManager(RackManager rackManager) {<a name="line.1154"></a>
-<span class="sourceLineNo">1155</span> this.rackManager = rackManager;<a name="line.1155"></a>
-<span class="sourceLineNo">1156</span> }<a name="line.1156"></a>
-<span class="sourceLineNo">1157</span><a name="line.1157"></a>
-<span class="sourceLineNo">1158</span> protected boolean needsBalance(Cluster c) {<a name="line.1158"></a>
-<span class="sourceLineNo">1159</span> ClusterLoadState cs = new ClusterLoadState(c.clusterState);<a name="line.1159"></a>
-<span class="sourceLineNo">1160</span> if (cs.getNumServers() < MIN_SERVER_BALANCE) {<a name="line.1160"></a>
-<span class="sourceLineNo">1161</span> if (LOG.isDebugEnabled()) {<a name="line.1161"></a>
-<span class="sourceLineNo">1162</span> LOG.debug("Not running balancer because only " + cs.getNumServers()<a name="line.1162"></a>
-<span class="sourceLineNo">1163</span> + " active regionserver(s)");<a name="line.1163"></a>
-<span class="sourceLineNo">1164</span> }<a name="line.1164"></a>
-<span class="sourceLineNo">1165</span> return false;<a name="line.1165"></a>
-<span class="sourceLineNo">1166</span> }<a name="line.1166"></a>
-<span class="sourceLineNo">1167</span> if(areSomeRegionReplicasColocated(c)) return true;<a name="line.1167"></a>
-<span class="sourceLineNo">1168</span> // Check if we even need to do any load balancing<a name="line.1168"></a>
-<span class="sourceLineNo">1169</span> // HBASE-3681 check sloppiness first<a name="line.1169"></a>
-<span class="sourceLineNo">1170</span> float average = cs.getLoadAverage(); // for logging<a name="line.1170"></a>
-<span class="sourceLineNo">1171</span> int floor = (int) Math.floor(average * (1 - slop));<a name="line.1171"></a>
-<span class="sourceLineNo">1172</span> int ceiling = (int) Math.ceil(average * (1 + slop));<a name="line.1172"></a>
-<span class="sourceLineNo">1173</span> if (!(cs.getMaxLoad() > ceiling || cs.getMinLoad() < floor)) {<a name="line.1173"></a>
-<span class="sourceLineNo">1174</span> NavigableMap<ServerAndLoad, List<RegionInfo>> serversByLoad = cs.getServersByLoad();<a name="line.1174"></a>
-<span class="sourceLineNo">1175</span> if (LOG.isTraceEnabled()) {<a name="line.1175"></a>
-<span class="sourceLineNo">1176</span> // If nothing to balance, then don't say anything unless trace-level logging.<a name="line.1176"></a>
-<span class="sourceLineNo">1177</span> LOG.trace("Skipping load balancing because balanced cluster; " +<a name="line.1177"></a>
-<span class="sourceLineNo">1178</span> "servers=" + cs.getNumServers() +<a name="line.1178"></a>
-<span class="sourceLineNo">1179</span> " regions=" + cs.getNumRegions() + " average=" + average +<a name="line.1179"></a>
-<span class="sourceLineNo">1180</span> " mostloaded=" + serversByLoad.lastKey().getLoad() +<a name="line.1180"></a>
-<span class="sourceLineNo">1181</span> " leastloaded=" + serversByLoad.firstKey().getLoad());<a name="line.1181"></a>
-<span class="sourceLineNo">1182</span> }<a name="line.1182"></a>
-<span class="sourceLineNo">1183</span> return false;<a name="line.1183"></a>
-<span class="sourceLineNo">1184</span> }<a name="line.1184"></a>
-<span class="sourceLineNo">1185</span> return true;<a name="line.1185"></a>
-<span class="sourceLineNo">1186</span> }<a name="line.1186"></a>
-<span class="sourceLineNo">1187</span><a name="line.1187"></a>
-<span class="sourceLineNo">1188</span> /**<a name="line.1188"></a>
-<span class="sourceLineNo">1189</span> * Subclasses should implement this to return true if the cluster has nodes that hosts<a name="line.1189"></a>
-<span class="sourceLineNo">1190</span> * multiple replicas for the same region, or, if there are multiple racks and the same<a name="line.1190"></a>
-<span class="sourceLineNo">1191</span> * rack hosts replicas of the same region<a name="line.1191"></a>
-<span class="sourceLineNo">1192</span> * @param c Cluster information<a name="line.1192"></a>
-<span class="sourceLineNo">1193</span> * @return whether region replicas are currently co-located<a name="line.1193"></a>
-<span class="sourceLineNo">1194</span> */<a name="line.1194"></a>
-<span class="sourceLineNo">1195</span> protected boolean areSomeRegionReplicasColocated(Cluster c) {<a name="line.1195"></a>
-<span class="sourceLineNo">1196</span> return false;<a name="line.1196"></a>
-<span class="sourceLineNo">1197</span> }<a name="line.1197"></a>
-<span class="sourceLineNo">1198</span><a name="line.1198"></a>
-<span class="sourceLineNo">1199</span> /**<a name="line.1199"></a>
-<span class="sourceLineNo">1200</span> * Generates a bulk assignment plan to be used on cluster startup using a<a name="line.1200"></a>
-<span class="sourceLineNo">1201</span> * simple round-robin assignment.<a name="line.1201"></a>
-<span class="sourceLineNo">1202</span> * <p><a name="line.1202"></a>
-<span class="sourceLineNo">1203</span> * Takes a list of all the regions and all the servers in the cluster and<a name="line.1203"></a>
-<span class="sourceLineNo">1204</span> * returns a map of each server to the regions that it should be assigned.<a name="line.1204"></a>
-<span class="sourceLineNo">1205</span> * <p><a name="line.1205"></a>
-<span class="sourceLineNo">1206</span> * Currently implemented as a round-robin assignment. Same invariant as load<a name="line.1206"></a>
-<span class="sourceLineNo">1207</span> * balancing, all servers holding floor(avg) or ceiling(avg).<a name="line.1207"></a>
-<span class="sourceLineNo">1208</span> *<a name="line.1208"></a>
-<span class="sourceLineNo">1209</span> * TODO: Use block locations from HDFS to place regions with their blocks<a name="line.1209"></a>
-<span class="sourceLineNo">1210</span> *<a name="line.1210"></a>
-<span class="sourceLineNo">1211</span> * @param regions all regions<a name="line.1211"></a>
-<span class="sourceLineNo">1212</span> * @param servers all servers<a name="line.1212"></a>
-<span class="sourceLineNo">1213</span> * @return map of server to the regions it should take, or null if no<a name="line.1213"></a>
-<span class="sourceLineNo">1214</span> * assignment is possible (ie. no regions or no servers)<a name="line.1214"></a>
-<span class="sourceLineNo">1215</span> */<a name="line.1215"></a>
-<span class="sourceLineNo">1216</span> @Override<a name="line.1216"></a>
-<span class="sourceLineNo">1217</span> public Map<ServerName, List<RegionInfo>> roundRobinAssignment(List<RegionInfo> regions,<a name="line.1217"></a>
-<span class="sourceLineNo">1218</span> List<ServerName> servers) throws HBaseIOException {<a name="line.1218"></a>
-<span class="sourceLineNo">1219</span> metricsBalancer.incrMiscInvocations();<a name="line.1219"></a>
-<span class="sourceLineNo">1220</span> Map<ServerName, List<RegionInfo>> assignments = assignMasterSystemRegions(regions, servers);<a name="line.1220"></a>
-<span class="sourceLineNo">1221</span> if (assignments != null && !assignments.isEmpty()) {<a name="line.1221"></a>
-<span class="sourceLineNo">1222</span> servers = new ArrayList<>(servers);<a name="line.1222"></a>
-<span class="sourceLineNo">1223</span> // Guarantee not to put other regions on master<a name="line.1223"></a>
-<span class="sourceLineNo">1224</span> servers.remove(masterServerName);<a name="line.1224"></a>
-<span class="sourceLineNo">1225</span> List<RegionInfo> masterRegions = assignments.get(masterServerName);<a name="line.1225"></a>
-<span class="sourceLineNo">1226</span> if (!masterRegions.isEmpty()) {<a name="line.1226"></a>
-<span class="sourceLineNo">1227</span> regions = new ArrayList<>(regions);<a name="line.1227"></a>
-<span class="sourceLineNo">1228</span> regions.removeAll(masterRegions);<a name="line.1228"></a>
-<span class="sourceLineNo">1229</span> }<a name="line.1229"></a>
-<span class="sourceLineNo">1230</span> }<a name="line.1230"></a>
-<span class="sourceLineNo">1231</span> if (regions == null || regions.isEmpty()) {<a name="line.1231"></a>
-<span class="sourceLineNo">1232</span> return assignments;<a name="line.1232"></a>
-<span class="sourceLineNo">1233</span> }<a name="line.1233"></a>
-<span class="sourceLineNo">1234</span><a name="line.1234"></a>
-<span class="sourceLineNo">1235</span> int numServers = servers == null ? 0 : servers.size();<a name="line.1235"></a>
-<span class="sourceLineNo">1236</span> if (numServers == 0) {<a name="line.1236"></a>
-<span class="sourceLineNo">1237</span> LOG.warn("Wanted to do round robin assignment but no servers to assign to");<a name="line.1237"></a>
-<span class="sourceLineNo">1238</span> return null;<a name="line.1238"></a>
-<span class="sourceLineNo">1239</span> }<a name="line.1239"></a>
-<span class="sourceLineNo">1240</span><a name="line.1240"></a>
-<span class="sourceLineNo">1241</span> // TODO: instead of retainAssignment() and roundRobinAssignment(), we should just run the<a name="line.1241"></a>
-<span class="sourceLineNo">1242</span> // normal LB.balancerCluster() with unassignedRegions. We only need to have a candidate<a name="line.1242"></a>
-<span class="sourceLineNo">1243</span> // generator for AssignRegionAction. The LB will ensure the regions are mostly local<a name="line.1243"></a>
-<span class="sourceLineNo">1244</span> // and balanced. This should also run fast with fewer number of iterations.<a name="line.1244"></a>
-<span class="sourceLineNo">1245</span><a name="line.1245"></a>
-<span class="sourceLineNo">1246</span> if (numServers == 1) { // Only one server, nothing fancy we can do here<a name="line.1246"></a>
-<span class="sourceLineNo">1247</span> ServerName server = servers.get(0);<a name="line.1247"></a>
-<span class="sourceLineNo">1248</span> assignments.put(server, new ArrayList<>(regions));<a name="line.1248"></a>
-<span class="sourceLineNo">1249</span> return assignments;<a name="line.1249"></a>
-<span class="sourceLineNo">1250</span> }<a name="line.1250"></a>
-<span class="sourceLineNo">1251</span><a name="line.1251"></a>
-<span class="sourceLineNo">1252</span> Cluster cluster = createCluster(servers, regions, false);<a name="line.1252"></a>
-<span class="sourceLineNo">1253</span> List<RegionInfo> unassignedRegions = new ArrayList<>();<a name="line.1253"></a>
-<span class="sourceLineNo">1254</span><a name="line.1254"></a>
-<span class="sourceLineNo">1255</span> roundRobinAssignment(cluster, regions, unassignedRegions,<a name="line.1255"></a>
-<span class="sourceLineNo">1256</span> servers, assignments);<a name="line.1256"></a>
-<span class="sourceLineNo">1257</span><a name="line.1257"></a>
-<span class="sourceLineNo">1258</span> List<RegionInfo> lastFewRegions = new ArrayList<>();<a name="line.1258"></a>
-<span class="sourceLineNo">1259</span> // assign the remaining by going through the list and try to assign to servers one-by-one<a name="line.1259"></a>
-<span class="sourceLineNo">1260</span> int serverIdx = RANDOM.nextInt(numServers);<a name="line.1260"></a>
-<span class="sourceLineNo">1261</span> for (RegionInfo region : unassignedRegions) {<a name="line.1261"></a>
-<span class="sourceLineNo">1262</span> boolean assigned = false;<a name="line.1262"></a>
-<span class="sourceLineNo">1263</span> for (int j = 0; j < numServers; j++) { // try all servers one by one<a name="line.1263"></a>
-<span class="sourceLineNo">1264</span> ServerName serverName = servers.get((j + serverIdx) % numServers);<a name="line.1264"></a>
-<span class="sourceLineNo">1265</span> if (!cluster.wouldLowerAvailability(region, serverName)) {<a name="line.1265"></a>
-<span class="sourceLineNo">1266</span> List<RegionInfo> serverRegions =<a name="line.1266"></a>
-<span class="sourceLineNo">1267</span> assignments.computeIfAbsent(serverName, k -> new ArrayList<>());<a name="line.1267"></a>
-<span class="sourceLineNo">1268</span> serverRegions.add(region);<a name="line.1268"></a>
-<span class="sourceLineNo">1269</span> cluster.doAssignRegion(region, serverName);<a name="line.1269"></a>
-<span class="sourceLineNo">1270</span> serverIdx = (j + serverIdx + 1) % numServers; //remain from next server<a name="line.1270"></a>
-<span class="sourceLineNo">1271</span> assigned = true;<a name="line.1271"></a>
-<span class="sourceLineNo">1272</span> break;<a name="line.1272"></a>
-<span class="sourceLineNo">1273</span> }<a name="line.1273"></a>
-<span class="sourceLineNo">1274</span> }<a name="line.1274"></a>
-<span class="sourceLineNo">1275</span> if (!assigned) {<a name="line.1275"></a>
-<span class="sourceLineNo">1276</span> lastFewRegions.add(region);<a name="line.1276"></a>
-<span class="sourceLineNo">1277</span> }<a name="line.1277"></a>
-<span class="sourceLineNo">1278</span> }<a name="line.1278"></a>
-<span class="sourceLineNo">1279</span> // just sprinkle the rest of the regions on random regionservers. The balanceCluster will<a name="line.1279"></a>
-<span class="sourceLineNo">1280</span> // make it optimal later. we can end up with this if numReplicas > numServers.<a name="line.1280"></a>
-<span class="sourceLineNo">1281</span> for (RegionInfo region : lastFewRegions) {<a name="line.1281"></a>
-<span class="sourceLineNo">1282</span> int i = RANDOM.nextInt(numServers);<a name="line.1282"></a>
-<span class="sourceLineNo">1283</span> ServerName server = servers.get(i);<a name="line.1283"></a>
-<span class="sourceLineNo">1284</span> List<RegionInfo> serverRegions = assignments.computeIfAbsent(server, k -> new ArrayList<>());<a name="line.1284"></a>
-<span class="sourceLineNo">1285</span> serverRegions.add(region);<a name="line.1285"></a>
-<span class="sourceLineNo">1286</span> cluster.doAssignRegion(region, server);<a name="line.1286"></a>
-<span class="sourceLineNo">1287</span> }<a name="line.1287"></a>
-<span class="sourceLineNo">1288</span> return assignments;<a name="line.1288"></a>
-<span class="sourceLineNo">1289</span> }<a name="line.1289"></a>
-<span class="sourceLineNo">1290</span><a name="line.1290"></a>
-<span class="sourceLineNo">1291</span> protected Cluster createCluster(List<ServerName> servers,<a name="line.1291"></a>
-<span class="sourceLineNo">1292</span> Collection<RegionInfo> regions, boolean forceRefresh) {<a name="line.1292"></a>
-<span class="sourceLineNo">1293</span> if (forceRefresh && useRegionFinder) {<a name="line.1293"></a>
-<span class="sourceLineNo">1294</span> regionFinder.refreshAndWait(regions);<a name="line.1294"></a>
-<span class="sourceLineNo">1295</span> }<a name="line.1295"></a>
-<span class="sourceLineNo">1296</span> // Get the snapshot of the current assignments for the regions in question, and then create<a name="line.1296"></a>
-<span class="sourceLineNo">1297</span> // a cluster out of it. Note that we might have replicas already assigned to some servers<a name="line.1297"></a>
-<span class="sourceLineNo">1298</span> // earlier. So we want to get the snapshot to see those assignments, but this will only contain<a name="line.1298"></a>
-<span class="sourceLineNo">1299</span> // replicas of the regions that are passed (for performance).<a name="line.1299"></a>
-<span class="sourceLineNo">1300</span> Map<ServerName, List<RegionInfo>> clusterState = getRegionAssignmentsByServer(regions);<a name="line.1300"></a>
-<span class="sourceLineNo">1301</span><a name="line.1301"></a>
-<span class="sourceLineNo">1302</span> for (ServerName server : servers) {<a name="line.1302"></a>
-<span class="sourceLineNo">1303</span> if (!clusterState.containsKey(server)) {<a name="line.1303"></a>
-<span class="sourceLineNo">1304</span> clusterState.put(server, EMPTY_REGION_LIST);<a name="line.1304"></a>
-<span class="sourceLineNo">1305</span> }<a name="line.1305"></a>
-<span class="sourceLineNo">1306</span> }<a name="line.1306"></a>
-<span class="sourceLineNo">1307</span> return new Cluster(regions, clusterState, null, this.regionFinder,<a name="line.1307"></a>
-<span class="sourceLineNo">1308</span> rackManager);<a name="line.1308"></a>
-<span class="sourceLineNo">1309</span> }<a name="line.1309"></a>
+<span class="sourceLineNo">1154</span> @Override<a name="line.1154"></a>
+<span class="sourceLineNo">1155</span> public void postMasterStartupInitialize() {<a name="line.1155"></a>
+<span class="sourceLineNo">1156</span> if (services != null && regionFinder != null) {<a name="line.1156"></a>
+<span class="sourceLineNo">1157</span> try {<a name="line.1157"></a>
+<span class="sourceLineNo">1158</span> Set<RegionInfo> regions =<a name="line.1158"></a>
+<span class="sourceLineNo">1159</span> services.getAssignmentManager().getRegionStates().getRegionAssignments().keySet();<a name="line.1159"></a>
+<span class="sourceLineNo">1160</span> regionFinder.refreshAndWait(regions);<a name="line.1160"></a>
+<span class="sourceLineNo">1161</span> } catch (Exception e) {<a name="line.1161"></a>
+<span class="sourceLineNo">1162</span> LOG.warn("Refreshing region HDFS Block dist failed with exception, ignoring", e);<a name="line.1162"></a>
+<span class="sourceLineNo">1163</span> }<a name="line.1163"></a>
+<span class="sourceLineNo">1164</span> }<a name="line.1164"></a>
+<span class="sourceLineNo">1165</span> }<a name="line.1165"></a>
+<span class="sourceLineNo">1166</span><a name="line.1166"></a>
+<span class="sourceLineNo">1167</span> public void setRackManager(RackManager rackManager) {<a name="line.1167"></a>
+<span class="sourceLineNo">1168</span> this.rackManager = rackManager;<a name="line.1168"></a>
+<span class="sourceLineNo">1169</span> }<a name="line.1169"></a>
+<span class="sourceLineNo">1170</span><a name="line.1170"></a>
+<span class="sourceLineNo">1171</span> protected boolean needsBalance(Cluster c) {<a name="line.1171"></a>
+<span class="sourceLineNo">1172</span> ClusterLoadState cs = new ClusterLoadState(c.clusterState);<a name="line.1172"></a>
+<span class="sourceLineNo">1173</span> if (cs.getNumServers() < MIN_SERVER_BALANCE) {<a name="line.1173"></a>
+<span class="sourceLineNo">1174</span> if (LOG.isDebugEnabled()) {<a name="line.1174"></a>
+<span class="sourceLineNo">1175</span> LOG.debug("Not running balancer because only " + cs.getNumServers()<a name="line.1175"></a>
+<span class="sourceLineNo">1176</span> + " active regionserver(s)");<a name="line.1176"></a>
+<span class="sourceLineNo">1177</span> }<a name="line.1177"></a>
+<span class="sourceLineNo">1178</span> return false;<a name="line.1178"></a>
+<span class="sourceLineNo">1179</span> }<a name="line.1179"></a>
+<span class="sourceLineNo">1180</span> if(areSomeRegionReplicasColocated(c)) return true;<a name="line.1180"></a>
+<span class="sourceLineNo">1181</span> // Check if we even need to do any load balancing<a name="line.1181"></a>
+<span class="sourceLineNo">1182</span> // HBASE-3681 check sloppiness first<a name="line.1182"></a>
+<span class="sourceLineNo">1183</span> float average = cs.getLoadAverage(); // for logging<a name="line.1183"></a>
+<span class="sourceLineNo">1184</span> int floor = (int) Math.floor(average * (1 - slop));<a name="line.1184"></a>
+<span class="sourceLineNo">1185</span> int ceiling = (int) Math.ceil(average * (1 + slop));<a name="line.1185"></a>
+<span class="sourceLineNo">1186</span> if (!(cs.getMaxLoad() > ceiling || cs.getMinLoad() < floor)) {<a name="line.1186"></a>
+<span class="sourceLineNo">1187</span> NavigableMap<ServerAndLoad, List<RegionInfo>> serversByLoad = cs.getServersByLoad();<a name="line.1187"></a>
+<span class="sourceLineNo">1188</span> if (LOG.isTraceEnabled()) {<a name="line.1188"></a>
+<span class="sourceLineNo">1189</span> // If nothing to balance, then don't say anything unless trace-level logging.<a name="line.1189"></a>
+<span class="sourceLineNo">1190</span> LOG.trace("Skipping load balancing because balanced cluster; " +<a name="line.1190"></a>
+<span class="sourceLineNo">1191</span> "servers=" + cs.getNumServers() +<a name="line.1191"></a>
+<span class="sourceLineNo">1192</span> " regions=" + cs.getNumRegions() + " average=" + average +<a name="line.1192"></a>
+<span class="sourceLineNo">1193</span> " mostloaded=" + serversByLoad.lastKey().getLoad() +<a name="line.1193"></a>
+<span class="sourceLineNo">1194</span> " leastloaded=" + serversByLoad.firstKey().getLoad());<a name="line.1194"></a>
+<span class="sourceLineNo">1195</span> }<a name="line.1195"></a>
+<span class="sourceLineNo">1196</span> return false;<a name="line.1196"></a>
+<span class="sourceLineNo">1197</span> }<a name="line.1197"></a>
+<span class="sourceLineNo">1198</span> return true;<a name="line.1198"></a>
+<span class="sourceLineNo">1199</span> }<a name="line.1199"></a>
+<span class="sourceLineNo">1200</span><a name="line.1200"></a>
+<span class="sourceLineNo">1201</span> /**<a name="line.1201"></a>
+<span class="sourceLineNo">1202</span> * Subclasses should implement this to return true if the cluster has nodes that hosts<a name="line.1202"></a>
+<span class="sourceLineNo">1203</span> * multiple replicas for the same region, or, if there are multiple racks and the same<a name="line.1203"></a>
+<span class="sourceLineNo">1204</span> * rack hosts replicas of the same region<a name="line.1204"></a>
+<span class="sourceLineNo">1205</span> * @param c Cluster information<a name="line.1205"></a>
+<span class="sourceLineNo">1206</span> * @return whether region replicas are currently co-located<a name="line.1206"></a>
+<span class="sourceLineNo">1207</span> */<a name="line.1207"></a>
+<span class="sourceLineNo">1208</span> protected boolean areSomeRegionReplicasColocated(Cluster c) {<a name="line.1208"></a>
+<span class="sourceLineNo">1209</span> return false;<a name="line.1209"></a>
+<span class="sourceLineNo">1210</span> }<a name="line.1210"></a>
+<span class="sourceLineNo">1211</span><a name="line.1211"></a>
+<span class="sourceLineNo">1212</span> /**<a name="line.1212"></a>
+<span class="sourceLineNo">1213</span> * Generates a bulk assignment plan to be used on cluster startup using a<a name="line.1213"></a>
+<span class="sourceLineNo">1214</span> * simple round-robin assignment.<a name="line.1214"></a>
+<span class="sourceLineNo">1215</span> * <p><a name="line.1215"></a>
+<span class="sourceLineNo">1216</span> * Takes a list of all the regions and all the servers in the cluster and<a name="line.1216"></a>
+<span class="sourceLineNo">1217</span> * returns a map of each server to the regions that it should be assigned.<a name="line.1217"></a>
+<span class="sourceLineNo">1218</span> * <p><a name="line.1218"></a>
+<span class="sourceLineNo">1219</span> * Currently implemented as a round-robin assignment. Same invariant as load<a name="line.1219"></a>
+<span class="sourceLineNo">1220</span> * balancing, all servers holding floor(avg) or ceiling(avg).<a name="line.1220"></a>
+<span class="sourceLineNo">1221</span> *<a name="line.1221"></a>
+<span class="sourceLineNo">1222</span> * TODO: Use block locations from HDFS to place regions with their blocks<a name="line.1222"></a>
+<span class="sourceLineNo">1223</span> *<a name="line.1223"></a>
+<span class="sourceLineNo">1224</span> * @param regions all regions<a name="line.1224"></a>
+<span class="sourceLineNo">1225</span> * @param servers all servers<a name="line.1225"></a>
+<span class="sourceLineNo">1226</span> * @return map of server to the regions it should take, or null if no<a name="line.1226"></a>
+<span class="sourceLineNo">1227</span> * assignment is possible (ie. no regions or no servers)<a name="line.1227"></a>
+<span class="sourceLineNo">1228</span> */<a name="line.1228"></a>
+<span class="sourceLineNo">1229</span> @Override<a name="line.1229"></a>
+<span class="sourceLineNo">1230</span> public Map<ServerName, List<RegionInfo>> roundRobinAssignment(List<RegionInfo> regions,<a name="line.1230"></a>
+<span class="sourceLineNo">1231</span> List<ServerName> servers) throws HBaseIOException {<a name="line.1231"></a>
+<span class="sourceLineNo">1232</span> metricsBalancer.incrMiscInvocations();<a name="line.1232"></a>
+<span class="sourceLineNo">1233</span> Map<ServerName, List<RegionInfo>> assignments = assignMasterSystemRegions(regions, servers);<a name="line.1233"></a>
+<span class="sourceLineNo">1234</span> if (assignments != null && !assignments.isEmpty()) {<a name="line.1234"></a>
+<span class="sourceLineNo">1235</span> servers = new ArrayList<>(servers);<a name="line.1235"></a>
+<span class="sourceLineNo">1236</span> // Guarantee not to put other regions on master<a name="line.1236"></a>
+<span class="sourceLineNo">1237</span> servers.remove(masterServerName);<a name="line.1237"></a>
+<span class="sourceLineNo">1238</span> List<RegionInfo> masterRegions = assignments.get(masterServerName);<a name="line.1238"></a>
+<span class="sourceLineNo">1239</span> if (!masterRegions.isEmpty()) {<a name="line.1239"></a>
+<span class="sourceLineNo">1240</span> regions = new ArrayList<>(regions);<a name="line.1240"></a>
+<span class="sourceLineNo">1241</span> regions.removeAll(masterRegions);<a name="line.1241"></a>
+<span class="sourceLineNo">1242</span> }<a name="line.1242"></a>
+<span class="sourceLineNo">1243</span> }<a name="line.1243"></a>
+<span class="sourceLineNo">1244</span> if (regions == null || regions.isEmpty()) {<a name="line.1244"></a>
+<span class="sourceLineNo">1245</span> return assignments;<a name="line.1245"></a>
+<span class="sourceLineNo">1246</span> }<a name="line.1246"></a>
+<span class="sourceLineNo">1247</span><a name="line.1247"></a>
+<span class="sourceLineNo">1248</span> int numServers = servers == null ? 0 : servers.size();<a name="line.1248"></a>
+<span class="sourceLineNo">1249</span> if (numServers == 0) {<a name="line.1249"></a>
+<span class="sourceLineNo">1250</span> LOG.warn("Wanted to do round robin assignment but no servers to assign to");<a name="line.1250"></a>
+<span class="sourceLineNo">1251</span> return null;<a name="line.1251"></a>
+<span class="sourceLineNo">1252</span> }<a name="line.1252"></a>
+<span class="sourceLineNo">1253</span><a name="line.1253"></a>
+<span class="sourceLineNo">1254</span> // TODO: instead of retainAssignment() and roundRobinAssignment(), we should just run the<a name="line.1254"></a>
+<span class="sourceLineNo">1255</span> // normal LB.balancerCluster() with unassignedRegions. We only need to have a candidate<a name="line.1255"></a>
+<span class="sourceLineNo">1256</span> // generator for AssignRegionAction. The LB will ensure the regions are mostly local<a name="line.1256"></a>
+<span class="sourceLineNo">1257</span> // and balanced. This should also run fast with fewer number of iterations.<a name="line.1257"></a>
+<span class="sourceLineNo">1258</span><a name="line.1258"></a>
+<span class="sourceLineNo">1259</span> if (numServers == 1) { // Only one server, nothing fancy we can do here<a name="line.1259"></a>
+<span class="sourceLineNo">1260</span> ServerName server = servers.get(0);<a name="line.1260"></a>
+<span class="sourceLineNo">1261</span> assignments.put(server, new ArrayList<>(regions));<a name="line.1261"></a>
+<span class="sourceLineNo">1262</span> return assignments;<a name="line.1262"></a>
+<span class="sourceLineNo">1263</span> }<a name="line.1263"></a>
+<span class="sourceLineNo">1264</span><a name="line.1264"></a>
+<span class="sourceLineNo">1265</span> Cluster cluster = createCluster(servers, regions);<a name="line.1265"></a>
+<span class="sourceLineNo">1266</span> List<RegionInfo> unassignedRegions = new ArrayList<>();<a name="line.1266"></a>
+<span class="sourceLineNo">1267</span><a name="line.1267"></a>
+<span class="sourceLineNo">1268</span> roundRobinAssignment(cluster, regions, unassignedRegions,<a name="line.1268"></a>
+<span class="sourceLineNo">1269</span> servers, assignments);<a name="line.1269"></a>
+<span class="sourceLineNo">1270</span><a name="line.1270"></a>
+<span class="sourceLineNo">1271</span> List<RegionInfo> lastFewRegions = new ArrayList<>();<a name="line.1271"></a>
+<span class="sourceLineNo">1272</span> // assign the remaining by going through the list and try to assign to servers one-by-one<a name="line.1272"></a>
+<span class="sourceLineNo">1273</span> int serverIdx = RANDOM.nextInt(numServers);<a name="line.1273"></a>
+<span class="sourceLineNo">1274</span> for (RegionInfo region : unassignedRegions) {<a name="line.1274"></a>
+<span class="sourceLineNo">1275</span> boolean assigned = false;<a name="line.1275"></a>
+<span class="sourceLineNo">1276</span> for (int j = 0; j < numServers; j++) { // try all servers one by one<a name="line.1276"></a>
+<span class="sourceLineNo">1277</span> ServerName serverName = servers.get((j + serverIdx) % numServers);<a name="line.1277"></a>
+<span class="sourceLineNo">1278</span> if (!cluster.wouldLowerAvailability(region, serverName)) {<a name="line.1278"></a>
+<span class="sourceLineNo">1279</span> List<RegionInfo> serverRegions =<a name="line.1279"></a>
+<span class="sourceLineNo">1280</span> assignments.computeIfAbsent(serverName, k -> new ArrayList<>());<a name="line.1280"></a>
+<span class="sourceLineNo">1281</span> serverRegions.add(region);<a name="line.1281"></a>
+<span class="sourceLineNo">1282</span> cluster.doAssignRegion(region, serverName);<a name="line.1282"></a>
+<span class="sourceLineNo">1283</span> serverIdx = (j + serverIdx + 1) % numServers; //remain from next server<a name="line.1283"></a>
+<span class="sourceLineNo">1284</span> assigned = true;<a name="line.1284"></a>
+<span class="sourceLineNo">1285</span> break;<a name="line.1285"></a>
+<span class="sourceLineNo">1286</span> }<a name="line.1286"></a>
+<span class="sourceLineNo">1287</span> }<a name="line.1287"></a>
+<span class="sourceLineNo">1288</span> if (!assigned) {<a name="line.1288"></a>
+<span class="sourceLineNo">1289</span> lastFewRegions.add(region);<a name="line.1289"></a>
+<span class="sourceLineNo">1290</span> }<a name="line.1290"></a>
+<span class="sourceLineNo">1291</span> }<a name="line.1291"></a>
+<span class="sourceLineNo">1292</span> // just sprinkle the rest of the regions on random regionservers. The balanceCluster will<a name="line.1292"></a>
+<span class="sourceLineNo">1293</span> // make it optimal later. we can end up with this if numReplicas > numServers.<a name="line.1293"></a>
+<span class="sourceLineNo">1294</span> for (RegionInfo region : lastFewRegions) {<a name="line.1294"></a>
+<span class="sourceLineNo">1295</span> int i = RANDOM.nextInt(numServers);<a name="line.1295"></a>
+<span class="sourceLineNo">1296</span> ServerName server = servers.get(i);<a name="line.1296"></a>
+<span class="sourceLineNo">1297</span> List<RegionInfo> serverRegions = assignments.computeIfAbsent(server, k -> new ArrayList<>());<a name="line.1297"></a>
+<span class="sourceLineNo">1298</span> serverRegions.add(region);<a name="line.1298"></a>
+<span class="sourceLineNo">1299</span> cluster.doAssignRegion(region, server);<a name="line.1299"></a>
+<span class="sourceLineNo">1300</span> }<a name="line.1300"></a>
+<span class="sourceLineNo">1301</span> return assignments;<a name="line.1301"></a>
+<span class="sourceLineNo">1302</span> }<a name="line.1302"></a>
+<span class="sourceLineNo">1303</span><a name="line.1303"></a>
+<span class="sourceLineNo">1304</span> protected Cluster createCluster(List<ServerName> servers, Collection<RegionInfo> regions) {<a name="line.1304"></a>
+<span class="sourceLineNo">1305</span> // Get the snapshot of the current assignments for the regions in question, and then create<a name="line.1305"></a>
+<span class="sourceLineNo">1306</span> // a cluster out of it. Note that we might have replicas already assigned to some servers<a name="line.1306"></a>
+<span class="sourceLineNo">1307</span> // earlier. So we want to get the snapshot to see those assignments, but this will only contain<a name="line.1307"></a>
+<span class="sourceLineNo">1308</span> // replicas of the regions that are passed (for performance).<a name="line.1308"></a>
+<span class="sourceLineNo">1309</span> Map<ServerName, List<RegionInfo>> clusterState = getRegionAssignmentsByServer(regions);<a name="line.1309"></a>
<span class="sourceLineNo">1310</span><a name="line.1310"></a>
-<span class="sourceLineNo">1311</span> private List<ServerName> findIdleServers(List<ServerName> servers) {<a name="line.1311"></a>
-<span class="sourceLineNo">1312</span> return this.services.getServerManager()<a name="line.1312"></a>
-<span class="sourceLineNo">1313</span> .getOnlineServersListWithPredicator(servers, IDLE_SERVER_PREDICATOR);<a name="line.1313"></a>
-<span class="sourceLineNo">1314</span> }<a name="line.1314"></a>
-<span class="sourceLineNo">1315</span><a name="line.1315"></a>
-<span class="sourceLineNo">1316</span> /**<a name="line.1316"></a>
-<span class="sourceLineNo">1317</span> * Used to assign a single region to a random server.<a name="line.1317"></a>
-<span class="sourceLineNo">1318</span> */<a name="line.1318"></a>
-<span class="sourceLineNo">1319</span> @Override<a name="line.1319"></a>
-<span class="sourceLineNo">1320</span> public ServerName randomAssignment(RegionInfo regionInfo, List<ServerName> servers)<a name="line.1320"></a>
-<span class="sourceLineNo">1321</span> throws HBaseIOException {<a name="line.1321"></a>
-<span class="sourceLineNo">1322</span> metricsBalancer.incrMiscInvocations();<a name="line.1322"></a>
-<span class="sourceLineNo">1323</span> if (servers != null && servers.contains(masterServerName)) {<a name="line.1323"></a>
-<span class="sourceLineNo">1324</span> if (shouldBeOnMaster(regionInfo)) {<a name="line.1324"></a>
-<span class="sourceLineNo">1325</span> return masterServerName;<a name="line.1325"></a>
-<span class="sourceLineNo">1326</span> }<a name="line.1326"></a>
-<span class="sourceLineNo">1327</span> if (!LoadBalancer.isTablesOnMaster(getConf())) {<a name="line.1327"></a>
-<span class="sourceLineNo">1328</span> // Guarantee we do not put any regions on master<a name="line.1328"></a>
-<span class="sourceLineNo">1329</span> servers = new ArrayList<>(servers);<a name="line.1329"></a>
-<span class="sourceLineNo">1330</span> servers.remove(masterServerName);<a name="line.1330"></a>
-<span class="sourceLineNo">1331</span> }<a name="line.1331"></a>
-<span class="sourceLineNo">1332</span> }<a name="line.1332"></a>
-<span class="sourceLineNo">1333</span><a name="line.1333"></a>
-<span class="sourceLineNo">1334</span> int numServers = servers == null ? 0 : servers.size();<a name="line.1334"></a>
-<span class="sourceLineNo">1335</span> if (numServers == 0) {<a name="line.1335"></a>
-<span class="sourceLineNo">1336</span> LOG.warn("Wanted to retain assignment but no servers to assign to");<a name="line.1336"></a>
-<span class="sourceLineNo">1337</span> return null;<a name="line.1337"></a>
-<span class="sourceLineNo">1338</span> }<a name="line.1338"></a>
-<span class="sourceLineNo">1339</span> if (numServers == 1) { // Only one server, nothing fancy we can do here<a name="line.1339"></a>
-<span class="sourceLineNo">1340</span> return servers.get(0);<a name="line.1340"></a>
+<span class="sourceLineNo">1311</span> for (ServerName server : servers) {<a name="line.1311"></a>
+<span class="sourceLineNo">1312</span> if (!clusterState.containsKey(server)) {<a name="line.1312"></a>
+<span class="sourceLineNo">1313</span> clusterState.put(server, EMPTY_REGION_LIST);<a name="line.1313"></a>
+<span class="sourceLineNo">1314</span> }<a name="line.1314"></a>
+<span class="sourceLineNo">1315</span> }<a name="line.1315"></a>
+<span class="sourceLineNo">1316</span> return new Cluster(regions, clusterState, null, this.regionFinder,<a name="line.1316"></a>
+<span class="sourceLineNo">1317</span> rackManager);<a name="line.1317"></a>
+<span class="sourceLineNo">1318</span> }<a name="line.1318"></a>
+<span class="sourceLineNo">1319</span><a name="line.1319"></a>
+<span class="sourceLineNo">1320</span> private List<ServerName> findIdleServers(List<ServerName> servers) {<a name="line.1320"></a>
+<span class="sourceLineNo">1321</span> return this.services.getServerManager()<a name="line.1321"></a>
+<span class="sourceLineNo">1322</span> .getOnlineServersListWithPredicator(servers, IDLE_SERVER_PREDICATOR);<a name="line.1322"></a>
+<span class="sourceLineNo">1323</span> }<a name="line.1323"></a>
+<span class="sourceLineNo">1324</span><a name="line.1324"></a>
+<span class="sourceLineNo">1325</span> /**<a name="line.1325"></a>
+<span class="sourceLineNo">1326</span> * Used to assign a single region to a random server.<a name="line.1326"></a>
+<span class="sourceLineNo">1327</span> */<a name="line.1327"></a>
+<span class="sourceLineNo">1328</span> @Override<a name="line.1328"></a>
+<span class="sourceLineNo">1329</span> public ServerName randomAssignment(RegionInfo regionInfo, List<ServerName> servers)<a name="line.1329"></a>
+<span class="sourceLineNo">1330</span> throws HBaseIOException {<a name="line.1330"></a>
+<span class="sourceLineNo">1331</span> metricsBalancer.incrMiscInvocations();<a name="line.1331"></a>
+<span class="sourceLineNo">1332</span> if (servers != null && servers.contains(masterServerName)) {<a name="line.1332"></a>
+<span class="sourceLineNo">1333</span> if (shouldBeOnMaster(regionInfo)) {<a name="line.1333"></a>
+<span class="sourceLineNo">1334</span> return masterServerName;<a name="line.1334"></a>
+<span class="sourceLineNo">1335</span> }<a name="line.1335"></a>
+<span class="sourceLineNo">1336</span> if (!LoadBalancer.isTablesOnMaster(getConf())) {<a name="line.1336"></a>
+<span class="sourceLineNo">1337</span> // Guarantee we do not put any regions on master<a name="line.1337"></a>
+<span class="sourceLineNo">1338</span> servers = new ArrayList<>(servers);<a name="line.1338"></a>
+<span class="sourceLineNo">1339</span> servers.remove(masterServerName);<a name="line.1339"></a>
+<span class="sourceLineNo">1340</span> }<a name="line.1340"></a>
<span class="sourceLineNo">1341</span> }<a name="line.1341"></a>
-<span class="sourceLineNo">1342</span> List<ServerName> idleServers = findIdleServers(servers);<a name="line.1342"></a>
-<span class="sourceLineNo">1343</span> if (idleServers.size() == 1) {<a name="line.1343"></a>
-<span class="sourceLineNo">1344</span> return idleServers.get(0);<a name="line.1344"></a>
-<span class="sourceLineNo">1345</span> }<a name="line.1345"></a>
-<span class="sourceLineNo">1346</span> final List<ServerName> finalServers = idleServers.isEmpty() ?<a name="line.1346"></a>
-<span class="sourceLineNo">1347</span> servers : idleServers;<a name="line.1347"></a>
-<span class="sourceLineNo">1348</span> List<RegionInfo> regions = Lists.newArrayList(regionInfo);<a name="line.1348"></a>
-<span class="sourceLineNo">1349</span> Cluster cluster = createCluster(finalServers, regions, false);<a name="line.1349"></a>
-<span class="sourceLineNo">1350</span> return randomAssignment(cluster, regionInfo, finalServers);<a name="line.1350"></a>
-<span class="sourceLineNo">1351</span> }<a name="line.1351"></a>
-<span class="sourceLineNo">1352</span><a name="line.1352"></a>
-<span class="sourceLineNo">1353</span> /**<a name="line.1353"></a>
-<span class="sourceLineNo">1354</span> * Generates a bulk assignment startup plan, attempting to reuse the existing<a name="line.1354"></a>
-<span class="sourceLineNo">1355</span> * assignment information from META, but adjusting for the specified list of<a name="line.1355"></a>
-<span class="sourceLineNo">1356</span> * available/online servers available for assignment.<a name="line.1356"></a>
-<span class="sourceLineNo">1357</span> * <p><a name="line.1357"></a>
-<span class="sourceLineNo">1358</span> * Takes a map of all regions to their existing assignment from META. Also<a name="line.1358"></a>
-<span class="sourceLineNo">1359</span> * takes a list of online servers for regions to be assigned to. Attempts to<a name="line.1359"></a>
-<span class="sourceLineNo">1360</span> * retain all assignment, so in some instances initial assignment will not be<a name="line.1360"></a>
-<span class="sourceLineNo">1361</span> * completely balanced.<a name="line.1361"></a>
-<span class="sourceLineNo">1362</span> * <p><a name="line.1362"></a>
-<span class="sourceLineNo">1363</span> * Any leftover regions without an existing server to be assigned to will be<a name="line.1363"></a>
-<span class="sourceLineNo">1364</span> * assigned randomly to available servers.<a name="line.1364"></a>
-<span class="sourceLineNo">1365</span> *<a name="line.1365"></a>
-<span class="sourceLineNo">1366</span> * @param regions regions and existing assignment from meta<a name="line.1366"></a>
-<span class="sourceLineNo">1367</span> * @param servers available servers<a name="line.1367"></a>
-<span class="sourceLineNo">1368</span> * @return map of servers and regions to be assigned to them<a name="line.1368"></a>
-<span class="sourceLineNo">1369</span> */<a name="line.1369"></a>
-<span class="sourceLineNo">1370</span> @Override<a name="line.1370"></a>
-<span class="sourceLineNo">1371</span> public Map<ServerName, List<RegionInfo>> retainAssignment(Map<RegionInfo, ServerName> regions,<a name="line.1371"></a>
-<span class="sourceLineNo">1372</span> List<ServerName> servers) throws HBaseIOException {<a name="line.1372"></a>
-<span class="sourceLineNo">1373</span> // Update metrics<a name="line.1373"></a>
-<span class="sourceLineNo">1374</span> metricsBalancer.incrMiscInvocations();<a name="line.1374"></a>
-<span class="sourceLineNo">1375</span> Map<ServerName, List<RegionInfo>> assignments = assignMasterSystemRegions(regions.keySet(), servers);<a name="line.1375"></a>
-<span class="sourceLineNo">1376</span> if (assignments != null && !assignments.isEmpty()) {<a name="line.1376"></a>
-<span class="sourceLineNo">1377</span> servers = new ArrayList<>(servers);<a name="line.1377"></a>
-<span class="sourceLineNo">1378</span> // Guarantee not to put other regions on master<a name="line.1378"></a>
-<span class="sourceLineNo">1379</span> servers.remove(masterServerName);<a name="line.1379"></a>
-<span class="sourceLineNo">1380</span> List<RegionInfo> masterRegions = assignments.get(masterServerName);<a name="line.1380"></a>
-<span class="sourceLineNo">1381</span> regions = regions.entrySet().stream().filter(e -> !masterRegions.contains(e.getKey()))<a name="line.1381"></a>
-<span class="sourceLineNo">1382</span> .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));<a name="line.1382"></a>
-<span class="sourceLineNo">1383</span> }<a name="line.1383"></a>
-<span class="sourceLineNo">1384</span> if (regions.isEmpty()) {<a name="line.1384"></a>
-<span class="sourceLineNo">1385</span> return assignments;<a name="line.1385"></a>
-<span class="sourceLineNo">1386</span> }<a name="line.1386"></a>
-<span class="sourceLineNo">1387</span><a name="line.1387"></a>
-<span class="sourceLineNo">1388</span> int numServers = servers == null ? 0 : servers.size();<a name="line.1388"></a>
-<span class="sourceLineNo">1389</span> if (numServers == 0) {<a name="line.1389"></a>
-<span class="sourceLineNo">1390</span> LOG.warn("Wanted to do retain assignment but no servers to assign to");<a name="line.1390"></a>
-<span class="sourceLineNo">1391</span> return null;<a name="line.1391"></a>
+<span class="sourceLineNo">1342</span><a name="line.1342"></a>
+<span class="sourceLineNo">1343</span> int numServers = servers == null ? 0 : servers.size();<a name="line.1343"></a>
+<span class="sourceLineNo">1344</span> if (numServers == 0) {<a name="line.1344"></a>
+<span class="sourceLineNo">1345</span> LOG.warn("Wanted to retain assignment but no servers to assign to");<a name="line.1345"></a>
+<span class="sourceLineNo">1346</span> return null;<a name="line.1346"></a>
+<span class="sourceLineNo">1347</span> }<a name="line.1347"></a>
+<span class="sourceLineNo">1348</span> if (numServers == 1) { // Only one server, nothing fancy we can do here<a name="line.1348"></a>
+<span class="sourceLineNo">1349</span> return servers.get(0);<a name="line.1349"></a>
+<span class="sourceLineNo">1350</span> }<a name="line.1350"></a>
+<span class="sourceLineNo">1351</span> List<ServerName> idleServers = findIdleServers(servers);<a name="line.1351"></a>
+<span class="sourceLineNo">1352</span> if (idleServers.size() == 1) {<a name="line.1352"></a>
+<span class="sourceLineNo">1353</span> return idleServers.get(0);<a name="line.1353"></a>
+<span class="sourceLineNo">1354</span> }<a name="line.1354"></a>
+<span class="sourceLineNo">1355</span> final List<ServerName> finalServers = idleServers.isEmpty() ?<a name="line.1355"></a>
+<span class="sourceLineNo">1356</span> servers : idleServers;<a name="line.1356"></a>
+<span class="sourceLineNo">1357</span> List<RegionInfo> regions = Lists.newArrayList(regionInfo);<a name="line.1357"></a>
+<span class="sourceLineNo">1358</span> Cluster cluster = createCluster(finalServers, regions);<a name="line.1358"></a>
+<span class="sourceLineNo">1359</span> return randomAssignment(cluster, regionInfo, finalServers);<a name="line.1359"></a>
+<span class="sourceLineNo">1360</span> }<a name="line.1360"></a>
+<span class="sourceLineNo">1361</span><a name="line.1361"></a>
+<span class="sourceLineNo">1362</span> /**<a name="line.1362"></a>
+<span class="sourceLineNo">1363</span> * Generates a bulk assignment startup plan, attempting to reuse the existing<a name="line.1363"></a>
+<span class="sourceLineNo">1364</span> * assignment information from META, but adjusting for the specified list of<a name="line.1364"></a>
+<span class="sourceLineNo">1365</span> * available/online servers available for assignment.<a name="line.1365"></a>
+<span class="sourceLineNo">1366</span> * <p><a name="line.1366"></a>
+<span class="sourceLineNo">1367</span> * Takes a map of all regions to their existing assignment from META. Also<a name="line.1367"></a>
+<span class="sourceLineNo">1368</span> * takes a list of online servers for regions to be assigned to. Attempts to<a name="line.1368"></a>
+<span class="sourceLineNo">1369</span> * retain all assignment, so in some instances initial assignment will not be<a name="line.1369"></a>
+<span class="sourceLineNo">1370</span> * completely balanced.<a name="line.1370"></a>
+<span class="sourceLineNo">1371</span> * <p><a name="line.1371"></a>
+<span class="sourceLineNo">1372</span> * Any leftover regions without an existing server to be assigned to will be<a name="line.1372"></a>
+<span class="sourceLineNo">1373</span> * assigned randomly to available servers.<a name="line.1373"></a>
+<span class="sourceLineNo">1374</span> *<a name="line.1374"></a>
+<span class="sourceLineNo">1375</span> * @param regions regions and existing assignment from meta<a name="line.1375"></a>
+<span class="sourceLineNo">1376</span> * @param servers available servers<a name="line.1376"></a>
+<span class="sourceLineNo">1377</span> * @return map of servers and regions to be assigned to them<a name="line.1377"></a>
+<span class="sourceLineNo">1378</span> */<a name="line.1378"></a>
+<span class="sourceLineNo">1379</span> @Override<a name="line.1379"></a>
+<span class="sourceLineNo">1380</span> public Map<ServerName, List<RegionInfo>> retainAssignment(Map<RegionInfo, ServerName> regions,<a name="line.1380"></a>
+<span class="sourceLineNo">1381</span> List<ServerName> servers) throws HBaseIOException {<a name="line.1381"></a>
+<span class="sourceLineNo">1382</span> // Update metrics<a name="line.1382"></a>
+<span class="sourceLineNo">1383</span> metricsBalancer.incrMiscInvocations();<a name="line.1383"></a>
+<span class="sourceLineNo">1384</span> Map<ServerName, List<RegionInfo>> assignments = assignMasterSystemRegions(regions.keySet(), servers);<a name="line.1384"></a>
+<span class="sourceLineNo">1385</span> if (assignments != null && !assignments.isEmpty()) {<a name="line.1385"></a>
+<span class="sourceLineNo">1386</span> servers = new ArrayList<>(servers);<a name="line.1386"></a>
+<span class="sourceLineNo">1387</span> // Guarantee not to put other regions on master<a name="line.1387"></a>
+<span class="sourceLineNo">1388</span> servers.remove(masterServerName);<a name="line.1388"></a>
+<span class="sourceLineNo">1389</span> List<RegionInfo> masterRegions = assignments.get(masterServerName);<a name="line.1389"></a>
+<span class="sourceLineNo">1390</span> regions = regions.entrySet().stream().filter(e -> !masterRegions.contains(e.getKey()))<a name="line.1390"></a>
+<span class="sourceLineNo">1391</span> .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));<a name="line.1391"></a>
<span class="sourceLineNo">1392</span> }<a name="line.1392"></a>
-<span class="sourceLineNo">1393</span> if (numServers == 1) { // Only one server, nothing fancy we can do here<a name="line.1393"></a>
-<span class="sourceLineNo">1394</span> ServerName server = servers.get(0);<a name="line.1394"></a>
-<span class="sourceLineNo">1395</span> assignments.put(server, new ArrayList<>(regions.keySet()));<a name="line.1395"></a>
-<span class="sourceLineNo">1396</span> return assignments;<a name="line.1396"></a>
-<span class="sourceLineNo">1397</span> }<a name="line.1397"></a>
-<span class="sourceLineNo">1398</span><a name="line.1398"></a>
-<span class="sourceLineNo">1399</span> // Group all of the old assignments by their hostname.<a name="line.1399"></a>
-<span class="sourceLineNo">1400</span> // We can't group directly by ServerName since the servers all have<a name="line.1400"></a>
-<span class="sourceLineNo">1401</span> // new start-codes.<a name="line.1401"></a>
-<span class="sourceLineNo">1402</span><a name="line.1402"></a>
-<span class="sourceLineNo">1403</span> // Group the servers by their hostname. It's possible we have multiple<a name="line.1403"></a>
-<span class="sourceLineNo">1404</span> // servers on the same host on different ports.<a name="line.1404"></a>
-<span class="sourceLineNo">1405</span> ArrayListMultimap<String, ServerName> serversByHostname = ArrayListMultimap.create();<a name="line.1405"></a>
-<span class="sourceLineNo">1406</span> for (ServerName server : servers) {<a name="line.1406"></a>
-<span class="sourceLineNo">1407</span> assignments.put(server, new ArrayList<>());<a name="line.1407"></a>
-<span class="sourceLineNo">1408</span> serversByHostname.put(server.getHostnameLowerCase(), server);<a name="line.1408"></a>
-<span class="sourceLineNo">1409</span> }<a name="line.1409"></a>
-<span class="sourceLineNo">1410</span><a name="line.1410"></a>
-<span class="sourceLineNo">1411</span> // Collection of the hostnames that used to have regions<a name="line.1411"></a>
-<span class="sourceLineNo">1412</span> // assigned, but for which we no longer have any RS running<a name="line.1412"></a>
-<span class="sourceLineNo">1413</span> // after the cluster restart.<a name="line.1413"></a>
-<span class="sourceLineNo">1414</span> Set<String> oldHostsNoLongerPresent = Sets.newTreeSet();<a name="line.1414"></a>
-<span class="sourceLineNo">1415</span><a name="line.1415"></a>
-<span class="sourceLineNo">1416</span> // If the old servers aren't present, lets assign those regions later.<a name="line.1416"></a>
-<span class="sourceLineNo">1417</span> List<RegionInfo> randomAssignRegions = Lists.newArrayList();<a name="line.1417"></a>
-<span class="sourceLineNo">1418</span><a name="line.1418"></a>
-<span class="sourceLineNo">1419</span> int numRandomAssignments = 0;<a name="line.1419"></a>
-<span class="sourceLineNo">1420</span> int numRetainedAssigments = 0;<a name="line.1420"></a>
-<span class="sourceLineNo">1421</span><a name="line.1421"></a>
-<span class="sourceLineNo">1422</span> Cluster cluster = createCluster(servers, regions.keySet(), true);<a name="line.1422"></a>
-<span class="sourceLineNo">1423</span><a name="line.1423"></a>
-<span class="sourceLineNo">1424</span> for (Map.Entry<RegionInfo, ServerName> entry : regions.entrySet()) {<a name="line.1424"></a>
-<span class="sourceLineNo">1425</span> RegionInfo region = entry.getKey();<a name="line.1425"></a>
-<span class="sourceLineNo">1426</span> ServerName oldServerName = entry.getValue();<a name="line.1426"></a>
-<span class="sourceLineNo">1427</span> List<ServerName> localServers = new ArrayList<>();<a name="line.1427"></a>
-<span class="sourceLineNo">1428</span> if (oldServerName != null) {<a name="line.1428"></a>
-<span class="sourceLineNo">1429</span> localServers = serversByHostname.get(oldServerName.getHostnameLowerCase());<a name="line.1429"></a>
-<span class="sourceLineNo">1430</span> }<a name="line.1430"></a>
-<span class="sourceLineNo">1431</span> if (localServers.isEmpty()) {<a name="line.1431"></a>
-<span class="sourceLineNo">1432</span> // No servers on the new cluster match up with this hostname, assign randomly, later.<a name="line.1432"></a>
-<span class="sourceLineNo">1433</span> randomAssignRegions.add(region);<a name="line.1433"></a>
-<span class="sourceLineNo">1434</span> if (oldServerName != null) {<a name="line.1434"></a>
-<span class="sourceLineNo">1435</span> oldHostsNoLongerPresent.add(oldServerName.getHostnameLowerCase());<a name="line.1435"></a>
-<span class="sourceLineNo">1436</span> }<a name="line.1436"></a>
-<span class="sourceLineNo">1437</span> } else if (localServers.size() == 1) {<a name="line.1437"></a>
-<span class="sourceLineNo">1438</span> // the usual case - one new server on same host<a name="line.1438"></a>
-<span class="sourceLineNo">1439</span> ServerName target = localServers.get(0);<a name="line.1439"></a>
-<span class="sourceLineNo">1440</span> assignments.get(target).add(region);<a name="line.1440"></a>
-<span class="sourceLineNo">1441</span> numRetainedAssigments++;<a name="line.1441"></a>
-<span class="sourceLineNo">1442</span> } else {<a name="line.1442"></a>
-<span class="sourceLineNo">1443</span> // multiple new servers in the cluster on this same host<a name="line.1443"></a>
-<span class="sourceLineNo">1444</span> if (localServers.contains(oldServerName)) {<a name="line.1444"></a>
-<span class="sourceLineNo">1445</span> assignments.get(oldServerName).add(region);<a name="line.1445"></a>
-<span class="sourceLineNo">1446</span> numRetainedAssigments++;<a name="line.1446"></a>
-<span class="sourceLineNo">1447</span> } else {<a name="line.1447"></a>
-<span class="sourceLineNo">1448</span> ServerName target = null;<a name="line.1448"></a>
-<span class="sourceLineNo">1449</span> for (ServerName tmp : localServers) {<a name="line.1449"></a>
-<span class="sourceLineNo">1450</span> if (tmp.getPort() == oldServerName.getPort()) {<a name="line.1450"></a>
-<span class="sourceLineNo">1451</span> target = tmp;<a name="line.1451"></a>
-<span class="sourceLineNo">1452</span> assignments.get(tmp).add(region);<a name="line.1452"></a>
-<span class="sourceLineNo">1453</span> numRetainedAssigments++;<a name="line.1453"></a>
-<span class="sourceLineNo">1454</span> break;<a name="line.1454"></a>
-<span class="sourceLineNo">1455</span> }<a name="line.1455"></a>
-<span class="sourceLineNo">1456</span> }<a name="line.1456"></a>
-<span class="sourceLineNo">1457</span> if (target == null) {<a name="line.1457"></a>
-<span class="sourceLineNo">1458</span> randomAssignRegions.add(region);<a name="line.1458"></a>
-<span class="sourceLineNo">1459</span> }<a name="line.1459"></a>
-<span class="sourceLineNo">1460</span> }<a name="line.1460"></a>
-<span class="sourceLineNo">1461</span> }<a name="line.1461"></a>
-<span class="sourceLineNo">1462</span> }<a name="line.1462"></a>
-<span class="sourceLineNo">1463</span><a name="line.1463"></a>
-<span class="sourceLineNo">1464</span> // If servers from prior assignment aren't present, then lets do randomAssignment on regions.<a name="line.1464"></a>
-<span class="sourceLineNo">1465</span> if (randomAssignRegions.size() > 0) {<a name="line.1465"></a>
-<span class="sourceLineNo">1466</span> for (Map.Entry<ServerName, List<RegionInfo>> entry : assignments.entrySet()) {<a name="line.1466"></a>
-<span class="sourceLineNo">1467</span> ServerName sn = entry.getKey();<a name="line.1467"></a>
-<span class="sourceLineNo">1468</span> for (RegionInfo region : entry.getValue()) {<a name="line.1468"></a>
-<span class="sourceLineNo">1469</span> cluster.doAssignRegion(region, sn);<a name="line.1469"></a>
-<span class="sourceLineNo">1470</span> }<a name="line.1470"></a>
-<span class="sourceLineNo">1471</span> }<a name="line.1471"></a>
-<span class="sourceLineNo">1472</span> for (RegionInfo region : randomAssignRegions) {<a name="line.1472"></a>
-<span class="sourceLineNo">1473</span> ServerName target = randomAssignment(cluster, region, servers);<a name="line.1473"></a>
-<span class="sourceLineNo">1474</span> assignments.get(target).add(region);<a name="line.1474"></a>
-<span class="sourceLineNo">1475</span> cluster.doAssignRegion(region, target);<a name="line.1475"></a>
-<span class="sourceLineNo">1476</span> numRandomAssignments++;<a name="line.1476"></a>
-<span class="sourceLineNo">1477</span> }<a name="line.1477"></a>
-<span class="sourceLineNo">1478</span> }<a name="line.1478"></a>
-<span class="sourceLineNo">1479</span><a name="line.1479"></a>
-<span class="sourceLineNo">1480</span> String randomAssignMsg = "";<a name="line.1480"></a>
-<span class="sourceLineNo">1481</span> if (numRandomAssignments > 0) {<a name="line.1481"></a>
-<span class="sourceLineNo">1482</span> randomAssignMsg =<a name="line.1482"></a>
-<span class="sourceLineNo">1483</span> numRandomAssignments + " regions were assigned "<a name="line.1483"></a>
-<span class="sourceLineNo">1484</span> + "to random hosts, since the old hosts for these regions are no "<a name="line.1484"></a>
-<span class="sourceLineNo">1485</span> + "longer present in the cluster. These hosts were:\n "<a name="line.1485"></a>
-<span class="sourceLineNo">1486</span> + Joiner.on("\n ").join(oldHostsNoLongerPresent);<a name="line.1486"></a>
-<span class="sourceLineNo">1487</span> }<a name="line.1487"></a>
-<span class="sourceLineNo">1488</span><a name="line.1488"></a>
-<span class="sourceLineNo">1489</span> LOG.info("Reassigned " + regions.size() + " regions. " + numRetainedAssigments<a name="line.1489"></a>
-<span class="sourceLineNo">1490</span> + " retained the pre-restart assignment. " + randomAssignMsg);<a name="line.1490"></a>
-<span class="sourceLineNo">1491</span> return assignments;<a name="line.1491"></a>
-<span class="sourceLineNo">1492</span> }<a name="line.1492"></a>
-<span class="sourceLineNo">1493</span><a name="line.1493"></a>
-<span class="sourceLineNo">1494</span> @Override<a name="line.1494"></a>
-<span class="sourceLineNo">1495</span> public void initialize() throws HBaseIOException{<a name="line.1495"></a>
-<span class="sourceLineNo">1496</span> }<a name="line.1496"></a>
-<span class="sourceLineNo">1497</span><a name="line.1497"></a>
-<span class="sourceLineNo">1498</span> @Override<a name="line.1498"></a>
-<span class="sourceLineNo">1499</span> public void regionOnline(RegionInfo regionInfo, ServerName sn) {<a name="line.1499"></a>
+<span class="sourceLineNo">1393</span> if (regions.isEmpty()) {<a name="line.1393"></a>
+<span class="sourceLineNo">1394</span> return assignments;<a name="line.1394"></a>
+<span class="sourceLineNo">1395</span> }<a name="line.1395"></a>
+<span class="sourceLineNo">1396</span><a name="line.1396"></a>
+<span class="sourceLineNo">1397</span> int numServers = servers == null ? 0 : servers.size();<a name="line.1397"></a>
+<span class="sourceLineNo">1398</span> if (numServers == 0) {<a name="line.1398"></a>
+<span class="sourceLineNo">1399</span> LOG.warn("Wanted to do retain assignment but no servers to assign to");<a name="line.1399"></a>
+<span class="sourceLineNo">1400</span> return null;<a name="line.1400"></a>
+<span class="sourceLineNo">1401</span> }<a name="line.1401"></a>
+<span class="sourceLineNo">1402</span> if (numServers == 1) { // Only one server, nothing fancy we can do here<a name="line.1402"></a>
+<span class="sourceLineNo">1403</span> ServerName server = servers.get(0);<a name="line.1403"></a>
+<span class="sourceLineNo">1404</span> assignments.put(server, new ArrayList<>(regions.keySet()));<a name="line.1404"></a>
+<span class="sourceLineNo">1405</span> return assignments;<a name="line.1405"></a>
+<span class="sourceLineNo">1406</span> }<a name="line.1406"></a>
+<span class="sourceLineNo">1407</span><a name="line.1407"></a>
+<span class="sourceLineNo">1408</span> // Group all of the old assignments by their hostname.<a name="line.1408"></a>
+<span class="sourceLineNo">1409</span> // We can't group directly by ServerName since the servers all have<a name="line.1409"></a>
+<span class="sourceLineNo">1410</span> // new start-codes.<a name="line.1410"></a>
+<span class="sourceLineNo">1411</span><a name="line.1411"></a>
+<span class="sourceLineNo">1412</span> // Group the servers by their hostname. It's possible we have multiple<a name="line.1412"></a>
+<span class="sourceLineNo">1413</span> // servers on the same host on different ports.<a name="line.1413"></a>
+<span class="sourceLineNo">1414</span> ArrayListMultimap<String, ServerName> serversByHostname = ArrayListMultimap.create();<a name="line.1414"></a>
+<span class="sourceLineNo">1415</span> for (ServerName server : servers) {<a name="line.1415"></a>
+<span class="sourceLineNo">1416</span> assignments.put(server, new ArrayList<>());<a name="line.1416"></a>
+<span class="sourceLineNo">1417</span> serversByHostname.put(server.getHostnameLowerCase(), server);<a name="line.1417"></a>
+<span class="sourceLineNo">1418</span> }<a name="line.1418"></a>
+<span class="sourceLineNo">1419</span><a name="line.1419"></a>
+<span class="sourceLineNo">1420</span> // Collection of the hostnames that used to have regions<a name="line.1420"></a>
+<span class="sourceLineNo">1421</span> // assigned, but for which we no longer have any RS running<a name="line.1421"></a>
+<span class="sourceLineNo">1422</span> // after the cluster restart.<a name="line.1422"></a>
+<span class="sourceLineNo">1423</span> Set<String> oldHostsNoLongerPresent = Sets.newTreeSet();<a name="line.1423"></a>
+<span class="sourceLineNo">1424</span><a name="line.1424"></a>
+<span class="sourceLineNo">1425</span> // If the old servers aren't present, lets assign those regions later.<a name="line.1425"></a>
+<span class="sourceLineNo">1426</span> List<RegionInfo> randomAssignRegions = Lists.newArrayList();<a name="line.1426"></a>
+<span class="sourceLineNo">1427</span><a name="line.1427"></a>
+<span class="sourceLineNo">1428</span> int numRandomAssignments = 0;<a name="line.1428"></a>
+<span class="sourceLineNo">1429</span> int numRetainedAssigments = 0;<a name="line.1429"></a>
+<span class="sourceLineNo">1430</span><a name="line.1430"></a>
+<span class="sourceLineNo">1431</span> for (Map.Entry<RegionInfo, ServerName> entry : regions.entrySet()) {<a name="line.1431"></a>
+<span class="sourceLineNo">1432</span> RegionInfo region = entry.getKey();<a name="line.1432"></a>
+<span class="sourceLineNo">1433</span> ServerName oldServerName = entry.getValue();<a name="line.1433"></a>
+<span class="sourceLineNo">1434</span> List<ServerName> localServers = new ArrayList<>();<a name="line.1434"></a>
+<span class="sourceLineNo">1435</span> if (oldServerName != null) {<a name="line.1435"></a>
+<span class="sourceLineNo">1436</span> localServers = serversByHostname.get(oldServerName.getHostnameLowerCase());<a name="line.1436"></a>
+<span class="sourceLineNo">1437</span> }<a name="line.1437"></a>
+<span class="sourceLineNo">1438</span> if (localServers.isEmpty()) {<a name="line.1438"></a>
+<span class="sourceLineNo">1439</span> // No servers on the new cluster match up with this hostname, assign randomly, later.<a name="line.1439"></a>
+<span class="sourceLineNo">1440</span> randomAssignRegions.add(region);<a name="line.1440"></a>
+<span class="sourceLineNo">1441</span> if (oldServerName != null) {<a name="line.1441"></a>
+<span class="sourceLineNo">1442</span> oldHostsNoLongerPresent.add(oldServerName.getHostnameLowerCase());<a name="line.1442"></a>
+<span class="sourceLineNo">1443</span> }<a name="line.1443"></a>
+<span class="sourceLineNo">1444</span> } else if (localServers.size() == 1) {<a name="line.1444"></a>
+<span class="sourceLineNo">1445</span> // the usual case - one new server on same host<a name="line.1445"></a>
+<span class="sourceLineNo">1446</span> ServerName target = localServers.get(0);<a name="line.1446"></a>
+<span class="sourceLineNo">1447</span> assignments.get(target).add(region);<a name="line.1447"></a>
+<span class="sourceLineNo">1448</span> numRetainedAssigments++;<a name="line.1448"></a>
+<span class="sourceLineNo">1449</span> } else {<a name="line.1449"></a>
+<span class="sourceLineNo">1450</span> // multiple new servers in the cluster on this same host<a name="line.1450"></a>
+<span class="sourceLineNo">1451</span> if (localServers.contains(oldServerName)) {<a name="line.1451"></a>
+<span class="sourceLineNo">1452</span> assignments.get(oldServerName).add(region);<a name="line.1452"></a>
+<span class="sourceLineNo">1453</span> numRetainedAssigments++;<a name="line.1453"></a>
+<span class="sourceLineNo">1454</span> } else {<a name="line.1454"></a>
+<span class="sourceLineNo">1455</span> ServerName target = null;<a name="line.1455"></a>
+<span class="sourceLineNo">1456</span> for (ServerName tmp : localServers) {<a name="line.1456"></a>
+<span class="sourceLineNo">1457</span> if (tmp.getPort() == oldServerName.getPort()) {<a name="line.1457"></a>
+<span class="sourceLineNo">1458</span> target = tmp;<a name="line.1458"></a>
+<span class="sourceLineNo">1459</span> assignments.get(tmp).add(region);<a name="line.1459"></a>
+<span class="sourceLineNo">1460</span> numRetainedAssigments++;<a name="line.1460"></a>
+<span class="sourceLineNo">1461</span> break;<a name="line.1461"></a>
+<span class="sourceLineNo">1462</span> }<a name="line.1462"></a>
+<span class="sourceLineNo">1463</span> }<a name="line.1463"></a>
+<span class="sourceLineNo">1464</span> if (target == null) {<a name="line.1464"></a>
+<span class="sourceLineNo">1465</span> randomAssignRegions.add(region);<a name="line.1465"></a>
+<span class="sourceLineNo">1466</span> }<a name="line.1466"></a>
+<span class="sourceLineNo">1467</span> }<a name="line.1467"></a>
+<span class="sourceLineNo">1468</span> }<a name="line.1468"></a>
+<span class="sourceLineNo">1469</span> }<a name="line.1469"></a>
+<span class="sourceLineNo">1470</span><a name="line.1470"></a>
+<span class="sourceLineNo">1471</span> // If servers from prior assignment aren't present, then lets do randomAssignment on regions.<a name="line.1471"></a>
+<span class="sourceLineNo">1472</span> if (randomAssignRegions.size() > 0) {<a name="line.1472"></a>
+<span class="sourceLineNo">1473</span> Cluster cluster = createCluster(servers, regions.keySet());<a name="line.1473"></a>
+<span class="sourceLineNo">1474</span> for (Map.Entry<ServerName, List<RegionInfo>> entry : assignments.entrySet()) {<a name="line.1474"></a>
+<span class="sourceLineNo">1475</span> ServerName sn = entry.getKey();<a name="line.1475"></a>
+<span class="sourceLineNo">1476</span> for (RegionInfo region : entry.getValue()) {<a name="line.1476"></a>
+<span class="sourceLineNo">1477</span> cluster.doAssignRegion(region, sn);<a name="line.1477"></a>
+<span class="sourceLineNo">1478</span> }<a name="line.1478"></a>
+<span class="sourceLineNo">1479</span> }<a name="line.1479"></a>
+<span class="sourceLineNo">1480</span> for (RegionInfo region : randomAssignRegions) {<a name="line.1480"></a>
+<span class="sourceLineNo">1481</span> ServerName target = randomAssignment(cluster, region, servers);<a name="line.1481"></a>
+<span class="sourceLineNo">1482</span> assignments.get(target).add(region);<a name="line.1482"></a>
+<span class="sourceLineNo">1483</span> cluster.doAssignRegion(region, target);<a name="line.1483"></a>
+<span class="sourceLineNo">1484</span> numRandomAssignments++;<a name="line.1484"></a>
+<span class="sourceLineNo">1485</span> }<a name="line.1485"></a>
+<span class="sourceLineNo">1486</span> }<a name="line.1486"></a>
+<span class="sourceLineNo">1487</span><a name="line.1487"></a>
+<span class="sourceLineNo">1488</span> String randomAssignMsg = "";<a name="line.1488"></a>
+<span class="sourceLineNo">1489</span> if (numRandomAssignments > 0) {<a name="line.1489"></a>
+<span class="sourceLineNo">1490</span> randomAssignMsg =<a name="line.1490"></a>
+<span class="sourceLineNo">1491</span> numRandomAssignments + " regions were assigned "<a name="line.1491"></a>
+<span class="sourceLineNo">1492</span> + "to random hosts, since the old hosts for these regions are no "<a name="line.1492"></a>
+<span class="sourceLineNo">1493</span> + "longer present in the cluster. These hosts were:\n "<a name="line.1493"></a>
+<span class="sourceLineNo">1494</span> + Joiner.on("\n ").join(oldHostsNoLongerPresent);<a name="line.1494"></a>
+<span class="sourceLineNo">1495</span> }<a name="line.1495"></a>
+<span class="sourceLineNo">1496</span><a name="line.1496"></a>
+<span class="sourceLineNo">1497</span> LOG.info("Reassigned " + regions.size() + " regions. " + numRetainedAssigments<a name="line.1497"></a>
+<span class="sourceLineNo">1498</span> + " retained the pre-restart assignment. " + randomAssignMsg);<a name="line.1498"></a>
+<span class="sourceLineNo">1499</span> return assignments;<a name="line.1499"></a>
<span class="sourceLineNo">1500</span> }<a name="line.1500"></a>
<span class="sourceLineNo">1501</span><a name="line.1501"></a>
<span class="sourceLineNo">1502</span> @Override<a name="line.1502"></a>
-<span class="sourceLineNo">1503</span> public void regionOffline(RegionInfo regionInfo) {<a name="line.1503"></a>
+<span class="sourceLineNo">1503</span> public void initialize() throws HBaseIOException{<a name="line.1503"></a>
<span class="sourceLineNo">1504</span> }<a name="line.1504"></a>
<span class="sourceLineNo">1505</span><a name="line.1505"></a>
<span class="sourceLineNo">1506</span> @Override<a name="line.1506"></a>
-<span class="sourceLineNo">1507</span> public boolean isStopped() {<a name="line.1507"></a>
-<span class="sourceLineNo">1508</span> return stopped;<a name="line.1508"></a>
-<span class="sourceLineNo">1509</span> }<a name="line.1509"></a>
-<span class="sourceLineNo">1510</span><a name="line.1510"></a>
-<span class="sourceLineNo">1511</span> @Override<a name="line.1511"></a>
-<span class="sourceLineNo">1512</span> public void stop(String why) {<a name="line.1512"></a>
-<span class="sourceLineNo">1513</span> LOG.info("Load Balancer stop requested: "+why);<a name="line.1513"></a>
-<span class="sourceLineNo">1514</span> stopped = true;<a name="line.1514"></a>
-<span class="sourceLineNo">1515</span> }<a name="line.1515"></a>
-<span class="sourceLineNo">1516</span><a name="line.1516"></a>
-<span class="sourceLineNo">1517</span> /**<a name="line.1517"></a>
-<span class="sourceLineNo">1518</span> * Used to assign a single region to a random server.<a name="line.1518"></a>
-<span class="sourceLineNo">1519</span> */<a name="line.1519"></a>
-<span class="sourceLineNo">1520</span> private ServerName randomAssignment(Cluster cluster, RegionInfo regionInfo,<a name="line.1520"></a>
-<span class="sourceLineNo">1521</span> List<ServerName> servers) {<a name="line.1521"></a>
-<span class="sourceLineNo">1522</span> int numServers = servers.size(); // servers is not null, numServers > 1<a name="line.1522"></a>
-<span class="sourceLineNo">1523</span> ServerName sn = null;<a name="line.1523"></a>
-<span class="sourceLineNo">1524</span> final int maxIterations = numServers * 4;<a name="line.1524"></a>
-<span class="sourceLineNo">1525</span> int iterations = 0;<a name="line.1525"></a>
-<span class="sourceLineNo">1526</span><a name="line.1526"></a>
-<span class="sourceLineNo">1527</span> do {<a name="line.1527"></a>
-<span class="sourceLineNo">1528</span> int i = RANDOM.nextInt(numServers);<a name="line.1528"></a>
-<span class="sourceLineNo">1529</span> sn = servers.get(i);<a name="line.1529"></a>
-<span class="sourceLineNo">1530</span> } while (cluster.wouldLowerAvailability(regionInfo, sn)<a name="line.1530"></a>
-<span class="sourceLineNo">1531</span> && iterations++ < maxIterations);<a name="line.1531"></a>
-<span class="sourceLineNo">1532</span> cluster.doAssignRegion(regionInfo, sn);<a name="line.1532"></a>
-<span class="sourceLineNo">1533</span> return sn;<a name="line.1533"></a>
-<span class="sourceLineNo">1534</span> }<a name="line.1534"></a>
-<span class="sourceLineNo">1535</span><a name="line.1535"></a>
-<span class="sourceLineNo">1536</span> /**<a name="line.1536"></a>
-<span class="sourceLineNo">1537</span> * Round robin a list of regions to a list of servers<a name="line.1537"></a>
-<span class="sourceLineNo">1538</span> */<a name="line.1538"></a>
-<span class="sourceLineNo">1539</span> private void roundRobinAssignment(Cluster cluster, List<RegionInfo> regions,<a name="line.1539"></a>
-<span class="sourceLineNo">1540</span> List<RegionInfo> unassignedRegions, List<ServerName> servers,<a name="line.1540"></a>
-<span class="sourceLineNo">1541</span> Map<ServerName, List<RegionInfo>> assignments) {<a name="line.1541"></a>
-<span class="sourceLineNo">1542</span><a name="line.1542"></a>
-<span class="sourceLineNo">1543</span> int numServers = servers.size();<a name="line.1543"></a>
-<span class="sourceLineNo">1544</span> int numRegions = regions.size();<a name="line.1544"></a>
-<span class="sourceLineNo">1545</span> int max = (int) Math.ceil((float) numRegions / numServers);<a name="line.1545"></a>
-<span class="sourceLineNo">1546</span> int serverIdx = 0;<a name="line.1546"></a>
-<span class="sourceLineNo">1547</span> if (numServers > 1) {<a name="line.1547"></a>
-<span class="sourceLineNo">1548</span> serverIdx = RANDOM.nextInt(numServers);<a name="line.1548"></a>
-<span class="sourceLineNo">1549</span> }<a name="line.1549"></a>
-<span class="sourceLineNo">1550</span> int regionIdx = 0;<a name="line.1550"></a>
-<span class="sourceLineNo">1551</span><a name="line.1551"></a>
-<span class="sourceLineNo">1552</span> for (int j = 0; j < numServers; j++) {<a name="line.1552"></a>
-<span class="sourceLineNo">1553</span> ServerName server = servers.get((j + serverIdx) % numServers);<a name="line.1553"></a>
-<span class="sourceLineNo">1554</span> List<RegionInfo> serverRegions = new ArrayList<>(max);<a name="line.1554"></a>
-<span class="sourceLineNo">1555</span> for (int i = regionIdx; i < numRegions; i += numServers) {<a name="line.1555"></a>
-<span class="sourceLineNo">1556</span> RegionInfo region = regions.get(i % numRegions);<a name="line.1556"></a>
-<span class="sourceLineNo">1557</span> if (cluster.wouldLowerAvailability(region, server)) {<a name="line.1557"></a>
-<span class="sourceLineNo">1558</span> unassignedRegions.add(region);<a name="line.1558"></a>
-<span class="sourceLineNo">1559</span> } else {<a name="line.1559"></a>
-<span class="sourceLineNo">1560</span> serverRegions.add(region);<a name="line.1560"></a>
-<span class="sourceLineNo">1561</span> cluster.doAssignRegion(region, server);<a name="line.1561"></a>
-<span class="sourceLineNo">1562</span> }<a name="line.1562"></a>
-<span class="sourceLineNo">1563</span> }<a name="line.1563"></a>
-<span class="sourceLineNo">1564</span> assignments.put(server, serverRegions);<a name="line.1564"></a>
-<span class="sourceLineNo">1565</span> regionIdx++;<a name="line.1565"></a>
-<span class="sourceLineNo">1566</span> }<a name="line.1566"></a>
-<span class="sourceLineNo">1567</span> }<a name="line.1567"></a>
-<span class="sourceLineNo">1568</span><a name="line.1568"></a>
-<span class="sourceLineNo">1569</span> protected Map<ServerName, List<RegionInfo>> getRegionAssignmentsByServer(<a name="line.1569"></a>
-<span class="sourceLineNo">1570</span> Collection<RegionInfo> regions) {<a name="line.1570"></a>
-<span class="sourceLineNo">1571</span> if (this.services != null && this.services.getAssignmentManager() != null) {<a name="line.1571"></a>
-<span class="sourceLineNo">1572</span> return this.services.getAssignmentManager().getSnapShotOfAssignment(regions);<a name="line.1572"></a>
-<span class="sourceLineNo">1573</span> } else {<a name="line.1573"></a>
-<span class="sourceLineNo">1574</span> return new HashMap<>();<a name="line.1574"></a>
-<span class="sourceLineNo">1575</span> }<a name="line.1575"></a>
-<span class="sourceLineNo">1576</span> }<a name="line.1576"></a>
-<span class="sourceLineNo">1577</span><a name="line.1577"></a>
-<span class="sourceLineNo">1578</span> @Override<a name="line.1578"></a>
-<span class="sourceLineNo">1579</span> public void onConfigurationChange(Configuration conf) {<a name="line.1579"></a>
-<span class="sourceLineNo">1580</span> }<a name="line.1580"></a>
-<span class="sourceLineNo">1581</span>}<a name="line.1581"></a>
+<span class="sourceLineNo">1507</span> public void regionOnline(RegionInfo regionInfo, ServerName sn) {<a name="line.1507"></a>
+<span class="sourceLineNo">1508</span> }<a name="line.1508"></a>
+<span class="sourceLineNo">1509</span><a name="line.1509"></a>
+<span class="sourceLineNo">1510</span> @Override<a name="line.1510"></a>
+<span class="sourceLineNo">1511</span> public void regionOffline(RegionInfo regionInfo) {<a name="line.1511"></a>
+<span class="sourceLineNo">1512</span> }<a name="line.1512"></a>
+<span class="sourceLineNo">1513</span><a name="line.1513"></a>
+<span class="sourceLineNo">1514</span> @Override<a name="line.1514"></a>
+<span class="sourceLineNo">1515</span> public boolean isStopped() {<a name="line.1515"></a>
+<span class="sourceLineNo">1516</span> return stopped;<a name="line.1516"></a>
+<span class="sourceLineNo">1517</span> }<a name="line.1517"></a>
+<span class="sourceLineNo">1518</span><a name="line.1518"></a>
+<span class="sourceLineNo">1519</span> @Override<a name="line.1519"></a>
+<span class="sourceLineNo">1520</span> public void stop(String why) {<a name="line.1520"></a>
+<span class="sourceLineNo">1521</span> LOG.info("Load Balancer stop requested: "+why);<a name="line.1521"></a>
+<span class="sourceLineNo">1522</span> stopped = true;<a name="line.1522"></a>
+<span class="sourceLineNo">1523</span> }<a name="line.1523"></a>
+<span class="sourceLineNo">1524</span><a name="line.1524"></a>
+<span class="sourceLineNo">1525</span> /**<a name="line.1525"></a>
+<span class="sourceLineNo">1526</span> * Used to assign a single region to a random server.<a name="line.1526"></a>
+<span class="sourceLineNo">1527</span> */<a name="line.1527"></a>
+<span class="sourceLineNo">1528</span> private ServerName randomAssignment(Cluster cluster, RegionInfo regionInfo,<a name="line.1528"></a>
+<span class="sourceLineNo">1529</span> List<ServerName> servers) {<a name="line.1529"></a>
+<span class="sourceLineNo">1530</span> int numServers = servers.size(); // servers is not null, numServers > 1<a name="line.1530"></a>
+<span class="sourceLineNo">1531</span> ServerName sn = null;<a name="line.1531"></a>
+<span class="sourceLineNo">1532</span> final int maxIterations = numServers * 4;<a name="line.1532"></a>
+<span class="sourceLineNo">1533</span> int iterations = 0;<a name="line.1533"></a>
+<span class="sourceLineNo">1534</span><a name="line.1534"></a>
+<span class="sourceLineNo">1535</span> do {<a name="line.1535"></a>
+<span class="sourceLineNo">1536</span> int i = RANDOM.nextInt(numServers);<a name="line.1536"></a>
+<span class="sourceLineNo">1537</span> sn = servers.get(i);<a name="line.1537"></a>
+<span class="sourceLineNo">1538</span> } while (cluster.wouldLowerAvailability(regionInfo, sn)<a name="line.1538"></a>
+<span class="sourceLineNo">1539</span> && iterations++ < maxIterations);<a name="line.1539"></a>
+<span class="sourceLineNo">1540</span> cluster.doAssignRegion(regionInfo, sn);<a name="line.1540"></a>
+<span class="sourceLineNo">1541</span> return sn;<a name="line.1541"></a>
+<span class="sourceLineNo">1542</span> }<a name="line.1542"></a>
+<span class="sourceLineNo">1543</span><a name="line.1543"></a>
+<span class="sourceLineNo">1544</span> /**<a name="line.1544"></a>
+<span class="sourceLineNo">1545</span> * Round robin a list of regions to a list of servers<a name="line.1545"></a>
+<span class="sourceLineNo">1546</span> */<a name="line.1546"></a>
+<span class="sourceLineNo">1547</span> private void roundRobinAssignment(Cluster cluster, List<RegionInfo> regions,<a name="line.1547"></a>
+<span class="sourceLineNo">1548</span> List<RegionInfo> unassignedRegions, List<ServerName> servers,<a name="line.1548"></a>
+<span class="sourceLineNo">1549</span> Map<ServerName, List<RegionInfo>> assignments) {<a name="line.1549"></a>
+<span class="sourceLineNo">1550</span><a name="line.1550"></a>
+<span class="sourceLineNo">1551</span> int numServers = servers.size();<a name="line.1551"></a>
+<span class="sourceLineNo">1552</span> int numRegions = regions.size();<a name="line.1552"></a>
+<span class="sourceLineNo">1553</span> int max = (int) Math.ceil((float) numRegions / numServers);<a name="line.1553"></a>
+<span class="sourceLineNo">1554</span> int serverIdx = 0;<a name="line.1554"></a>
+<span class="sourceLineNo">1555</span> if (numServers > 1) {<a name="line.1555"></a>
+<span class="sourceLineNo">1556</span> serverIdx = RANDOM.nextInt(numServers);<a name="line.1556"></a>
+<span class="sourceLineNo">1557</span> }<a name="line.1557"></a>
+<span class="sourceLineNo">1558</span> int regionIdx = 0;<a name="line.1558"></a>
+<span class="sourceLineNo">1559</span><a name="line.1559"></a>
+<span class="sourceLineNo">1560</span> for (int j = 0; j < numServers; j++) {<a name="line.1560"></a>
+<span class="sourceLineNo">1561</span> ServerName server = servers.get((j + serverIdx) % numServers);<a name="line.1561"></a>
+<span class="sourceLineNo">1562</span> List<RegionInfo> serverRegions = new ArrayList<>(max);<a name="line.1562"></a>
+<span class="sourceLineNo">1563</span> for (int i = regionIdx; i < numRegions; i += numServers) {<a name="line.1563"></a>
+<span class="sourceLineNo">1564</span> RegionInfo region = regions.get(i % numRegions);<a name="line.1564"></a>
+<span class="sourceLineNo">1565</span> if (cluster.wouldLowerAvailability(region, server)) {<a name="line.1565"></a>
+<span class="sourceLineNo">1566</span> unassignedRegions.add(region);<a name="line.1566"></a>
+<span class="sourceLineNo">1567</span> } else {<a name="line.1567"></a>
+<span class="sourceLineNo">1568</span> serverRegions.add(region);<a name="line.1568"></a>
+<span class="sourceLineNo">1569</span> cluster.doAssignRegion(region, server);<a name="line.1569"></a>
+<span class="sourceLineNo">1570</span> }<a name="line.1570"></a>
+<span class="sourceLineNo">1571</span> }<a name="line.1571"></a>
+<span class="sourceLineNo">1572</span> assignments.put(server, serverRegions);<a name="line.1572"></a>
+<span class="sourceLineNo">1573</span> regionIdx++;<a name="line.1573"></a>
+<span class="sourceLineNo">1574</span> }<a name="line.1574"></a>
+<span class="sourceLineNo">1575</span> }<a name="line.1575"></a>
+<span class="sourceLineNo">1576</span><a name="line.1576"></a>
+<span class="sourceLineNo">1577</span> protected Map<ServerName, List<RegionInfo>> getRegionAssignmentsByServer(<a name="line.1577"></a>
+<span class="sourceLineNo">1578</span> Collection<RegionInfo> regions) {<a name="line.1578"></a>
+<span class="sourceLineNo">1579</span> if (this.services != null && this.services.getAssignmentManager() != null) {<a name="line.1579"></a>
+<span class="sourceLineNo">1580</span> return this.services.getAssignmentManager().getSnapShotOfAssignment(regions);<a name="line.1580"></a>
+<span class="sourceLineNo">1581</span> } else {<a name="line.1581"></a>
+<span class="sourceLineNo">1582</span> return new HashMap<>();<a name="line.1582"></a>
+<span class="sourceLineNo">1583</span> }<a name="line.1583"></a>
+<span class="sourceLineNo">1584</span> }<a name="line.1584"></a>
+<span class="sourceLineNo">1585</span><a name="line.1585"></a>
+<span class="sourceLineNo">1586</span> @Override<a name="line.1586"></a>
+<span class="sourceLineNo">1587</span> public void onConfigurationChange(Configuration conf) {<a name="line.1587"></a>
+<span class="sourceLineNo">1588</span> }<a name="line.1588"></a>
+<span class="sourceLineNo">1589</span>}<a name="line.1589"></a>