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Posted to commits@hbase.apache.org by gi...@apache.org on 2018/07/03 20:06:22 UTC
[07/51] [partial] hbase-site git commit: Published site at
0f23784182ab88649de340d75804e0ff20dcd0fc.
http://git-wip-us.apache.org/repos/asf/hbase-site/blob/bcb555af/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/BlockCacheUtil.CachedBlockCountsPerFile.html
----------------------------------------------------------------------
diff --git a/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/BlockCacheUtil.CachedBlockCountsPerFile.html b/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/BlockCacheUtil.CachedBlockCountsPerFile.html
index f118c08..cd9722f 100644
--- a/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/BlockCacheUtil.CachedBlockCountsPerFile.html
+++ b/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/BlockCacheUtil.CachedBlockCountsPerFile.html
@@ -206,140 +206,175 @@
<span class="sourceLineNo">198</span> */<a name="line.198"></a>
<span class="sourceLineNo">199</span> public static int validateBlockAddition(Cacheable existing, Cacheable newBlock,<a name="line.199"></a>
<span class="sourceLineNo">200</span> BlockCacheKey cacheKey) {<a name="line.200"></a>
-<span class="sourceLineNo">201</span> int comparison = compareCacheBlock(existing, newBlock, true);<a name="line.201"></a>
+<span class="sourceLineNo">201</span> int comparison = compareCacheBlock(existing, newBlock, false);<a name="line.201"></a>
<span class="sourceLineNo">202</span> if (comparison != 0) {<a name="line.202"></a>
-<span class="sourceLineNo">203</span> LOG.warn("Cached block contents differ, trying to just compare the block contents " +<a name="line.203"></a>
-<span class="sourceLineNo">204</span> "without the next block. CacheKey: " + cacheKey);<a name="line.204"></a>
-<span class="sourceLineNo">205</span><a name="line.205"></a>
-<span class="sourceLineNo">206</span> // compare the contents, if they are not equal, we are in big trouble<a name="line.206"></a>
-<span class="sourceLineNo">207</span> int comparisonWithoutNextBlockMetadata = compareCacheBlock(existing, newBlock, false);<a name="line.207"></a>
-<span class="sourceLineNo">208</span><a name="line.208"></a>
-<span class="sourceLineNo">209</span> if (comparisonWithoutNextBlockMetadata != 0) {<a name="line.209"></a>
-<span class="sourceLineNo">210</span> throw new RuntimeException("Cached block contents differ, which should not have happened."<a name="line.210"></a>
-<span class="sourceLineNo">211</span> + "cacheKey:" + cacheKey);<a name="line.211"></a>
-<span class="sourceLineNo">212</span> }<a name="line.212"></a>
-<span class="sourceLineNo">213</span> }<a name="line.213"></a>
-<span class="sourceLineNo">214</span> return comparison;<a name="line.214"></a>
-<span class="sourceLineNo">215</span> }<a name="line.215"></a>
-<span class="sourceLineNo">216</span><a name="line.216"></a>
-<span class="sourceLineNo">217</span> /**<a name="line.217"></a>
-<span class="sourceLineNo">218</span> * Use one of these to keep a running account of cached blocks by file. Throw it away when done.<a name="line.218"></a>
-<span class="sourceLineNo">219</span> * This is different than metrics in that it is stats on current state of a cache.<a name="line.219"></a>
-<span class="sourceLineNo">220</span> * See getLoadedCachedBlocksByFile<a name="line.220"></a>
-<span class="sourceLineNo">221</span> */<a name="line.221"></a>
-<span class="sourceLineNo">222</span> @JsonIgnoreProperties({"cachedBlockStatsByFile"})<a name="line.222"></a>
-<span class="sourceLineNo">223</span> public static class CachedBlocksByFile {<a name="line.223"></a>
-<span class="sourceLineNo">224</span> private int count;<a name="line.224"></a>
-<span class="sourceLineNo">225</span> private int dataBlockCount;<a name="line.225"></a>
-<span class="sourceLineNo">226</span> private long size;<a name="line.226"></a>
-<span class="sourceLineNo">227</span> private long dataSize;<a name="line.227"></a>
-<span class="sourceLineNo">228</span> private final long now = System.nanoTime();<a name="line.228"></a>
-<span class="sourceLineNo">229</span> /**<a name="line.229"></a>
-<span class="sourceLineNo">230</span> * How many blocks to look at before we give up.<a name="line.230"></a>
-<span class="sourceLineNo">231</span> * There could be many millions of blocks. We don't want the<a name="line.231"></a>
-<span class="sourceLineNo">232</span> * ui to freeze while we run through 1B blocks... users will<a name="line.232"></a>
-<span class="sourceLineNo">233</span> * think hbase dead. UI displays warning in red when stats<a name="line.233"></a>
-<span class="sourceLineNo">234</span> * are incomplete.<a name="line.234"></a>
-<span class="sourceLineNo">235</span> */<a name="line.235"></a>
-<span class="sourceLineNo">236</span> private final int max;<a name="line.236"></a>
-<span class="sourceLineNo">237</span> public static final int DEFAULT_MAX = 1000000;<a name="line.237"></a>
-<span class="sourceLineNo">238</span><a name="line.238"></a>
-<span class="sourceLineNo">239</span> CachedBlocksByFile() {<a name="line.239"></a>
-<span class="sourceLineNo">240</span> this(null);<a name="line.240"></a>
-<span class="sourceLineNo">241</span> }<a name="line.241"></a>
-<span class="sourceLineNo">242</span><a name="line.242"></a>
-<span class="sourceLineNo">243</span> CachedBlocksByFile(final Configuration c) {<a name="line.243"></a>
-<span class="sourceLineNo">244</span> this.max = c == null? DEFAULT_MAX: c.getInt("hbase.ui.blockcache.by.file.max", DEFAULT_MAX);<a name="line.244"></a>
-<span class="sourceLineNo">245</span> }<a name="line.245"></a>
-<span class="sourceLineNo">246</span><a name="line.246"></a>
-<span class="sourceLineNo">247</span> /**<a name="line.247"></a>
-<span class="sourceLineNo">248</span> * Map by filename. use concurent utils because we want our Map and contained blocks sorted.<a name="line.248"></a>
-<span class="sourceLineNo">249</span> */<a name="line.249"></a>
-<span class="sourceLineNo">250</span> private NavigableMap<String, NavigableSet<CachedBlock>> cachedBlockByFile = new ConcurrentSkipListMap<>();<a name="line.250"></a>
-<span class="sourceLineNo">251</span> FastLongHistogram hist = new FastLongHistogram();<a name="line.251"></a>
-<span class="sourceLineNo">252</span><a name="line.252"></a>
-<span class="sourceLineNo">253</span> /**<a name="line.253"></a>
-<span class="sourceLineNo">254</span> * @param cb<a name="line.254"></a>
-<span class="sourceLineNo">255</span> * @return True if full.... if we won't be adding any more.<a name="line.255"></a>
-<span class="sourceLineNo">256</span> */<a name="line.256"></a>
-<span class="sourceLineNo">257</span> public boolean update(final CachedBlock cb) {<a name="line.257"></a>
-<span class="sourceLineNo">258</span> if (isFull()) return true;<a name="line.258"></a>
-<span class="sourceLineNo">259</span> NavigableSet<CachedBlock> set = this.cachedBlockByFile.get(cb.getFilename());<a name="line.259"></a>
-<span class="sourceLineNo">260</span> if (set == null) {<a name="line.260"></a>
-<span class="sourceLineNo">261</span> set = new ConcurrentSkipListSet<>();<a name="line.261"></a>
-<span class="sourceLineNo">262</span> this.cachedBlockByFile.put(cb.getFilename(), set);<a name="line.262"></a>
-<span class="sourceLineNo">263</span> }<a name="line.263"></a>
-<span class="sourceLineNo">264</span> set.add(cb);<a name="line.264"></a>
-<span class="sourceLineNo">265</span> this.size += cb.getSize();<a name="line.265"></a>
-<span class="sourceLineNo">266</span> this.count++;<a name="line.266"></a>
-<span class="sourceLineNo">267</span> BlockType bt = cb.getBlockType();<a name="line.267"></a>
-<span class="sourceLineNo">268</span> if (bt != null && bt.isData()) {<a name="line.268"></a>
-<span class="sourceLineNo">269</span> this.dataBlockCount++;<a name="line.269"></a>
-<span class="sourceLineNo">270</span> this.dataSize += cb.getSize();<a name="line.270"></a>
-<span class="sourceLineNo">271</span> }<a name="line.271"></a>
-<span class="sourceLineNo">272</span> long age = (this.now - cb.getCachedTime())/NANOS_PER_SECOND;<a name="line.272"></a>
-<span class="sourceLineNo">273</span> this.hist.add(age, 1);<a name="line.273"></a>
-<span class="sourceLineNo">274</span> return false;<a name="line.274"></a>
-<span class="sourceLineNo">275</span> }<a name="line.275"></a>
-<span class="sourceLineNo">276</span><a name="line.276"></a>
-<span class="sourceLineNo">277</span> /**<a name="line.277"></a>
-<span class="sourceLineNo">278</span> * @return True if full; i.e. there are more items in the cache but we only loaded up<a name="line.278"></a>
-<span class="sourceLineNo">279</span> * the maximum set in configuration <code>hbase.ui.blockcache.by.file.max</code><a name="line.279"></a>
-<span class="sourceLineNo">280</span> * (Default: DEFAULT_MAX).<a name="line.280"></a>
-<span class="sourceLineNo">281</span> */<a name="line.281"></a>
-<span class="sourceLineNo">282</span> public boolean isFull() {<a name="line.282"></a>
-<span class="sourceLineNo">283</span> return this.count >= this.max;<a name="line.283"></a>
-<span class="sourceLineNo">284</span> }<a name="line.284"></a>
-<span class="sourceLineNo">285</span><a name="line.285"></a>
-<span class="sourceLineNo">286</span> public NavigableMap<String, NavigableSet<CachedBlock>> getCachedBlockStatsByFile() {<a name="line.286"></a>
-<span class="sourceLineNo">287</span> return this.cachedBlockByFile;<a name="line.287"></a>
-<span class="sourceLineNo">288</span> }<a name="line.288"></a>
-<span class="sourceLineNo">289</span><a name="line.289"></a>
-<span class="sourceLineNo">290</span> /**<a name="line.290"></a>
-<span class="sourceLineNo">291</span> * @return count of blocks in the cache<a name="line.291"></a>
-<span class="sourceLineNo">292</span> */<a name="line.292"></a>
-<span class="sourceLineNo">293</span> public int getCount() {<a name="line.293"></a>
-<span class="sourceLineNo">294</span> return count;<a name="line.294"></a>
-<span class="sourceLineNo">295</span> }<a name="line.295"></a>
-<span class="sourceLineNo">296</span><a name="line.296"></a>
-<span class="sourceLineNo">297</span> public int getDataCount() {<a name="line.297"></a>
-<span class="sourceLineNo">298</span> return dataBlockCount;<a name="line.298"></a>
-<span class="sourceLineNo">299</span> }<a name="line.299"></a>
-<span class="sourceLineNo">300</span><a name="line.300"></a>
-<span class="sourceLineNo">301</span> /**<a name="line.301"></a>
-<span class="sourceLineNo">302</span> * @return size of blocks in the cache<a name="line.302"></a>
-<span class="sourceLineNo">303</span> */<a name="line.303"></a>
-<span class="sourceLineNo">304</span> public long getSize() {<a name="line.304"></a>
-<span class="sourceLineNo">305</span> return size;<a name="line.305"></a>
-<span class="sourceLineNo">306</span> }<a name="line.306"></a>
-<span class="sourceLineNo">307</span><a name="line.307"></a>
-<span class="sourceLineNo">308</span> /**<a name="line.308"></a>
-<span class="sourceLineNo">309</span> * @return Size of data.<a name="line.309"></a>
-<span class="sourceLineNo">310</span> */<a name="line.310"></a>
-<span class="sourceLineNo">311</span> public long getDataSize() {<a name="line.311"></a>
-<span class="sourceLineNo">312</span> return dataSize;<a name="line.312"></a>
-<span class="sourceLineNo">313</span> }<a name="line.313"></a>
-<span class="sourceLineNo">314</span><a name="line.314"></a>
-<span class="sourceLineNo">315</span> public AgeSnapshot getAgeInCacheSnapshot() {<a name="line.315"></a>
-<span class="sourceLineNo">316</span> return new AgeSnapshot(this.hist);<a name="line.316"></a>
-<span class="sourceLineNo">317</span> }<a name="line.317"></a>
-<span class="sourceLineNo">318</span><a name="line.318"></a>
-<span class="sourceLineNo">319</span> @Override<a name="line.319"></a>
-<span class="sourceLineNo">320</span> public String toString() {<a name="line.320"></a>
-<span class="sourceLineNo">321</span> AgeSnapshot snapshot = getAgeInCacheSnapshot();<a name="line.321"></a>
-<span class="sourceLineNo">322</span> return "count=" + count + ", dataBlockCount=" + dataBlockCount + ", size=" + size +<a name="line.322"></a>
-<span class="sourceLineNo">323</span> ", dataSize=" + getDataSize() +<a name="line.323"></a>
-<span class="sourceLineNo">324</span> ", mean age=" + snapshot.getMean() +<a name="line.324"></a>
-<span class="sourceLineNo">325</span> ", min age=" + snapshot.getMin() +<a name="line.325"></a>
-<span class="sourceLineNo">326</span> ", max age=" + snapshot.getMax() +<a name="line.326"></a>
-<span class="sourceLineNo">327</span> ", 75th percentile age=" + snapshot.get75thPercentile() +<a name="line.327"></a>
-<span class="sourceLineNo">328</span> ", 95th percentile age=" + snapshot.get95thPercentile() +<a name="line.328"></a>
-<span class="sourceLineNo">329</span> ", 98th percentile age=" + snapshot.get98thPercentile() +<a name="line.329"></a>
-<span class="sourceLineNo">330</span> ", 99th percentile age=" + snapshot.get99thPercentile() +<a name="line.330"></a>
-<span class="sourceLineNo">331</span> ", 99.9th percentile age=" + snapshot.get99thPercentile();<a name="line.331"></a>
-<span class="sourceLineNo">332</span> }<a name="line.332"></a>
-<span class="sourceLineNo">333</span> }<a name="line.333"></a>
-<span class="sourceLineNo">334</span>}<a name="line.334"></a>
+<span class="sourceLineNo">203</span> throw new RuntimeException("Cached block contents differ, which should not have happened."<a name="line.203"></a>
+<span class="sourceLineNo">204</span> + "cacheKey:" + cacheKey);<a name="line.204"></a>
+<span class="sourceLineNo">205</span> }<a name="line.205"></a>
+<span class="sourceLineNo">206</span> if ((existing instanceof HFileBlock) && (newBlock instanceof HFileBlock)) {<a name="line.206"></a>
+<span class="sourceLineNo">207</span> comparison = ((HFileBlock) existing).getNextBlockOnDiskSize()<a name="line.207"></a>
+<span class="sourceLineNo">208</span> - ((HFileBlock) newBlock).getNextBlockOnDiskSize();<a name="line.208"></a>
+<span class="sourceLineNo">209</span> }<a name="line.209"></a>
+<span class="sourceLineNo">210</span> return comparison;<a name="line.210"></a>
+<span class="sourceLineNo">211</span> }<a name="line.211"></a>
+<span class="sourceLineNo">212</span><a name="line.212"></a>
+<span class="sourceLineNo">213</span> /**<a name="line.213"></a>
+<span class="sourceLineNo">214</span> * Because of the region splitting, it's possible that the split key locate in the middle of a<a name="line.214"></a>
+<span class="sourceLineNo">215</span> * block. So it's possible that both the daughter regions load the same block from their parent<a name="line.215"></a>
+<span class="sourceLineNo">216</span> * HFile. When pread, we don't force the read to read all of the next block header. So when two<a name="line.216"></a>
+<span class="sourceLineNo">217</span> * threads try to cache the same block, it's possible that one thread read all of the next block<a name="line.217"></a>
+<span class="sourceLineNo">218</span> * header but the other one didn't. if the already cached block hasn't next block header but the<a name="line.218"></a>
+<span class="sourceLineNo">219</span> * new block to cache has, then we can replace the existing block with the new block for better<a name="line.219"></a>
+<span class="sourceLineNo">220</span> * performance.(HBASE-20447)<a name="line.220"></a>
+<span class="sourceLineNo">221</span> * @param blockCache BlockCache to check<a name="line.221"></a>
+<span class="sourceLineNo">222</span> * @param cacheKey the block cache key<a name="line.222"></a>
+<span class="sourceLineNo">223</span> * @param newBlock the new block which try to put into the block cache.<a name="line.223"></a>
+<span class="sourceLineNo">224</span> * @return true means need to replace existing block with new block for the same block cache key.<a name="line.224"></a>
+<span class="sourceLineNo">225</span> * false means just keep the existing block.<a name="line.225"></a>
+<span class="sourceLineNo">226</span> */<a name="line.226"></a>
+<span class="sourceLineNo">227</span> public static boolean shouldReplaceExistingCacheBlock(BlockCache blockCache,<a name="line.227"></a>
+<span class="sourceLineNo">228</span> BlockCacheKey cacheKey, Cacheable newBlock) {<a name="line.228"></a>
+<span class="sourceLineNo">229</span> Cacheable existingBlock = blockCache.getBlock(cacheKey, false, false, false);<a name="line.229"></a>
+<span class="sourceLineNo">230</span> try {<a name="line.230"></a>
+<span class="sourceLineNo">231</span> int comparison = BlockCacheUtil.validateBlockAddition(existingBlock, newBlock, cacheKey);<a name="line.231"></a>
+<span class="sourceLineNo">232</span> if (comparison < 0) {<a name="line.232"></a>
+<span class="sourceLineNo">233</span> LOG.warn("Cached block contents differ by nextBlockOnDiskSize, the new block has "<a name="line.233"></a>
+<span class="sourceLineNo">234</span> + "nextBlockOnDiskSize set. Caching new block.");<a name="line.234"></a>
+<span class="sourceLineNo">235</span> return true;<a name="line.235"></a>
+<span class="sourceLineNo">236</span> } else if (comparison > 0) {<a name="line.236"></a>
+<span class="sourceLineNo">237</span> LOG.warn("Cached block contents differ by nextBlockOnDiskSize, the existing block has "<a name="line.237"></a>
+<span class="sourceLineNo">238</span> + "nextBlockOnDiskSize set, Keeping cached block.");<a name="line.238"></a>
+<span class="sourceLineNo">239</span> return false;<a name="line.239"></a>
+<span class="sourceLineNo">240</span> } else {<a name="line.240"></a>
+<span class="sourceLineNo">241</span> LOG.warn("Caching an already cached block: {}. This is harmless and can happen in rare "<a name="line.241"></a>
+<span class="sourceLineNo">242</span> + "cases (see HBASE-8547)",<a name="line.242"></a>
+<span class="sourceLineNo">243</span> cacheKey);<a name="line.243"></a>
+<span class="sourceLineNo">244</span> return false;<a name="line.244"></a>
+<span class="sourceLineNo">245</span> }<a name="line.245"></a>
+<span class="sourceLineNo">246</span> } finally {<a name="line.246"></a>
+<span class="sourceLineNo">247</span> // return the block since we need to decrement the count<a name="line.247"></a>
+<span class="sourceLineNo">248</span> blockCache.returnBlock(cacheKey, existingBlock);<a name="line.248"></a>
+<span class="sourceLineNo">249</span> }<a name="line.249"></a>
+<span class="sourceLineNo">250</span> }<a name="line.250"></a>
+<span class="sourceLineNo">251</span><a name="line.251"></a>
+<span class="sourceLineNo">252</span> /**<a name="line.252"></a>
+<span class="sourceLineNo">253</span> * Use one of these to keep a running account of cached blocks by file. Throw it away when done.<a name="line.253"></a>
+<span class="sourceLineNo">254</span> * This is different than metrics in that it is stats on current state of a cache.<a name="line.254"></a>
+<span class="sourceLineNo">255</span> * See getLoadedCachedBlocksByFile<a name="line.255"></a>
+<span class="sourceLineNo">256</span> */<a name="line.256"></a>
+<span class="sourceLineNo">257</span> @JsonIgnoreProperties({"cachedBlockStatsByFile"})<a name="line.257"></a>
+<span class="sourceLineNo">258</span> public static class CachedBlocksByFile {<a name="line.258"></a>
+<span class="sourceLineNo">259</span> private int count;<a name="line.259"></a>
+<span class="sourceLineNo">260</span> private int dataBlockCount;<a name="line.260"></a>
+<span class="sourceLineNo">261</span> private long size;<a name="line.261"></a>
+<span class="sourceLineNo">262</span> private long dataSize;<a name="line.262"></a>
+<span class="sourceLineNo">263</span> private final long now = System.nanoTime();<a name="line.263"></a>
+<span class="sourceLineNo">264</span> /**<a name="line.264"></a>
+<span class="sourceLineNo">265</span> * How many blocks to look at before we give up.<a name="line.265"></a>
+<span class="sourceLineNo">266</span> * There could be many millions of blocks. We don't want the<a name="line.266"></a>
+<span class="sourceLineNo">267</span> * ui to freeze while we run through 1B blocks... users will<a name="line.267"></a>
+<span class="sourceLineNo">268</span> * think hbase dead. UI displays warning in red when stats<a name="line.268"></a>
+<span class="sourceLineNo">269</span> * are incomplete.<a name="line.269"></a>
+<span class="sourceLineNo">270</span> */<a name="line.270"></a>
+<span class="sourceLineNo">271</span> private final int max;<a name="line.271"></a>
+<span class="sourceLineNo">272</span> public static final int DEFAULT_MAX = 1000000;<a name="line.272"></a>
+<span class="sourceLineNo">273</span><a name="line.273"></a>
+<span class="sourceLineNo">274</span> CachedBlocksByFile() {<a name="line.274"></a>
+<span class="sourceLineNo">275</span> this(null);<a name="line.275"></a>
+<span class="sourceLineNo">276</span> }<a name="line.276"></a>
+<span class="sourceLineNo">277</span><a name="line.277"></a>
+<span class="sourceLineNo">278</span> CachedBlocksByFile(final Configuration c) {<a name="line.278"></a>
+<span class="sourceLineNo">279</span> this.max = c == null? DEFAULT_MAX: c.getInt("hbase.ui.blockcache.by.file.max", DEFAULT_MAX);<a name="line.279"></a>
+<span class="sourceLineNo">280</span> }<a name="line.280"></a>
+<span class="sourceLineNo">281</span><a name="line.281"></a>
+<span class="sourceLineNo">282</span> /**<a name="line.282"></a>
+<span class="sourceLineNo">283</span> * Map by filename. use concurent utils because we want our Map and contained blocks sorted.<a name="line.283"></a>
+<span class="sourceLineNo">284</span> */<a name="line.284"></a>
+<span class="sourceLineNo">285</span> private NavigableMap<String, NavigableSet<CachedBlock>> cachedBlockByFile = new ConcurrentSkipListMap<>();<a name="line.285"></a>
+<span class="sourceLineNo">286</span> FastLongHistogram hist = new FastLongHistogram();<a name="line.286"></a>
+<span class="sourceLineNo">287</span><a name="line.287"></a>
+<span class="sourceLineNo">288</span> /**<a name="line.288"></a>
+<span class="sourceLineNo">289</span> * @param cb<a name="line.289"></a>
+<span class="sourceLineNo">290</span> * @return True if full.... if we won't be adding any more.<a name="line.290"></a>
+<span class="sourceLineNo">291</span> */<a name="line.291"></a>
+<span class="sourceLineNo">292</span> public boolean update(final CachedBlock cb) {<a name="line.292"></a>
+<span class="sourceLineNo">293</span> if (isFull()) return true;<a name="line.293"></a>
+<span class="sourceLineNo">294</span> NavigableSet<CachedBlock> set = this.cachedBlockByFile.get(cb.getFilename());<a name="line.294"></a>
+<span class="sourceLineNo">295</span> if (set == null) {<a name="line.295"></a>
+<span class="sourceLineNo">296</span> set = new ConcurrentSkipListSet<>();<a name="line.296"></a>
+<span class="sourceLineNo">297</span> this.cachedBlockByFile.put(cb.getFilename(), set);<a name="line.297"></a>
+<span class="sourceLineNo">298</span> }<a name="line.298"></a>
+<span class="sourceLineNo">299</span> set.add(cb);<a name="line.299"></a>
+<span class="sourceLineNo">300</span> this.size += cb.getSize();<a name="line.300"></a>
+<span class="sourceLineNo">301</span> this.count++;<a name="line.301"></a>
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+<span class="sourceLineNo">306</span> }<a name="line.306"></a>
+<span class="sourceLineNo">307</span> long age = (this.now - cb.getCachedTime())/NANOS_PER_SECOND;<a name="line.307"></a>
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+<span class="sourceLineNo">312</span> /**<a name="line.312"></a>
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+<span class="sourceLineNo">320</span><a name="line.320"></a>
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+<span class="sourceLineNo">341</span> }<a name="line.341"></a>
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+<span class="sourceLineNo">348</span> }<a name="line.348"></a>
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+<span class="sourceLineNo">352</span> }<a name="line.352"></a>
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http://git-wip-us.apache.org/repos/asf/hbase-site/blob/bcb555af/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/BlockCacheUtil.CachedBlocksByFile.html
----------------------------------------------------------------------
diff --git a/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/BlockCacheUtil.CachedBlocksByFile.html b/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/BlockCacheUtil.CachedBlocksByFile.html
index f118c08..cd9722f 100644
--- a/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/BlockCacheUtil.CachedBlocksByFile.html
+++ b/devapidocs/src-html/org/apache/hadoop/hbase/io/hfile/BlockCacheUtil.CachedBlocksByFile.html
@@ -206,140 +206,175 @@
<span class="sourceLineNo">198</span> */<a name="line.198"></a>
<span class="sourceLineNo">199</span> public static int validateBlockAddition(Cacheable existing, Cacheable newBlock,<a name="line.199"></a>
<span class="sourceLineNo">200</span> BlockCacheKey cacheKey) {<a name="line.200"></a>
-<span class="sourceLineNo">201</span> int comparison = compareCacheBlock(existing, newBlock, true);<a name="line.201"></a>
+<span class="sourceLineNo">201</span> int comparison = compareCacheBlock(existing, newBlock, false);<a name="line.201"></a>
<span class="sourceLineNo">202</span> if (comparison != 0) {<a name="line.202"></a>
-<span class="sourceLineNo">203</span> LOG.warn("Cached block contents differ, trying to just compare the block contents " +<a name="line.203"></a>
-<span class="sourceLineNo">204</span> "without the next block. CacheKey: " + cacheKey);<a name="line.204"></a>
-<span class="sourceLineNo">205</span><a name="line.205"></a>
-<span class="sourceLineNo">206</span> // compare the contents, if they are not equal, we are in big trouble<a name="line.206"></a>
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-<span class="sourceLineNo">219</span> * This is different than metrics in that it is stats on current state of a cache.<a name="line.219"></a>
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-<span class="sourceLineNo">222</span> @JsonIgnoreProperties({"cachedBlockStatsByFile"})<a name="line.222"></a>
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-<span class="sourceLineNo">229</span> /**<a name="line.229"></a>
-<span class="sourceLineNo">230</span> * How many blocks to look at before we give up.<a name="line.230"></a>
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+<span class="sourceLineNo">212</span><a name="line.212"></a>
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+<span class="sourceLineNo">215</span> * block. So it's possible that both the daughter regions load the same block from their parent<a name="line.215"></a>
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+<span class="sourceLineNo">238</span> + "nextBlockOnDiskSize set, Keeping cached block.");<a name="line.238"></a>
+<span class="sourceLineNo">239</span> return false;<a name="line.239"></a>
+<span class="sourceLineNo">240</span> } else {<a name="line.240"></a>
+<span class="sourceLineNo">241</span> LOG.warn("Caching an already cached block: {}. This is harmless and can happen in rare "<a name="line.241"></a>
+<span class="sourceLineNo">242</span> + "cases (see HBASE-8547)",<a name="line.242"></a>
+<span class="sourceLineNo">243</span> cacheKey);<a name="line.243"></a>
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+<span class="sourceLineNo">251</span><a name="line.251"></a>
+<span class="sourceLineNo">252</span> /**<a name="line.252"></a>
+<span class="sourceLineNo">253</span> * Use one of these to keep a running account of cached blocks by file. Throw it away when done.<a name="line.253"></a>
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+<span class="sourceLineNo">257</span> @JsonIgnoreProperties({"cachedBlockStatsByFile"})<a name="line.257"></a>
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+<span class="sourceLineNo">260</span> private int dataBlockCount;<a name="line.260"></a>
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+<span class="sourceLineNo">262</span> private long dataSize;<a name="line.262"></a>
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+<span class="sourceLineNo">264</span> /**<a name="line.264"></a>
+<span class="sourceLineNo">265</span> * How many blocks to look at before we give up.<a name="line.265"></a>
+<span class="sourceLineNo">266</span> * There could be many millions of blocks. We don't want the<a name="line.266"></a>
+<span class="sourceLineNo">267</span> * ui to freeze while we run through 1B blocks... users will<a name="line.267"></a>
+<span class="sourceLineNo">268</span> * think hbase dead. UI displays warning in red when stats<a name="line.268"></a>
+<span class="sourceLineNo">269</span> * are incomplete.<a name="line.269"></a>
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+<span class="sourceLineNo">271</span> private final int max;<a name="line.271"></a>
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+<span class="sourceLineNo">273</span><a name="line.273"></a>
+<span class="sourceLineNo">274</span> CachedBlocksByFile() {<a name="line.274"></a>
+<span class="sourceLineNo">275</span> this(null);<a name="line.275"></a>
+<span class="sourceLineNo">276</span> }<a name="line.276"></a>
+<span class="sourceLineNo">277</span><a name="line.277"></a>
+<span class="sourceLineNo">278</span> CachedBlocksByFile(final Configuration c) {<a name="line.278"></a>
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+<span class="sourceLineNo">281</span><a name="line.281"></a>
+<span class="sourceLineNo">282</span> /**<a name="line.282"></a>
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+<span class="sourceLineNo">285</span> private NavigableMap<String, NavigableSet<CachedBlock>> cachedBlockByFile = new ConcurrentSkipListMap<>();<a name="line.285"></a>
+<span class="sourceLineNo">286</span> FastLongHistogram hist = new FastLongHistogram();<a name="line.286"></a>
+<span class="sourceLineNo">287</span><a name="line.287"></a>
+<span class="sourceLineNo">288</span> /**<a name="line.288"></a>
+<span class="sourceLineNo">289</span> * @param cb<a name="line.289"></a>
+<span class="sourceLineNo">290</span> * @return True if full.... if we won't be adding any more.<a name="line.290"></a>
+<span class="sourceLineNo">291</span> */<a name="line.291"></a>
+<span class="sourceLineNo">292</span> public boolean update(final CachedBlock cb) {<a name="line.292"></a>
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+<span class="sourceLineNo">294</span> NavigableSet<CachedBlock> set = this.cachedBlockByFile.get(cb.getFilename());<a name="line.294"></a>
+<span class="sourceLineNo">295</span> if (set == null) {<a name="line.295"></a>
+<span class="sourceLineNo">296</span> set = new ConcurrentSkipListSet<>();<a name="line.296"></a>
+<span class="sourceLineNo">297</span> this.cachedBlockByFile.put(cb.getFilename(), set);<a name="line.297"></a>
+<span class="sourceLineNo">298</span> }<a name="line.298"></a>
+<span class="sourceLineNo">299</span> set.add(cb);<a name="line.299"></a>
+<span class="sourceLineNo">300</span> this.size += cb.getSize();<a name="line.300"></a>
+<span class="sourceLineNo">301</span> this.count++;<a name="line.301"></a>
+<span class="sourceLineNo">302</span> BlockType bt = cb.getBlockType();<a name="line.302"></a>
+<span class="sourceLineNo">303</span> if (bt != null && bt.isData()) {<a name="line.303"></a>
+<span class="sourceLineNo">304</span> this.dataBlockCount++;<a name="line.304"></a>
+<span class="sourceLineNo">305</span> this.dataSize += cb.getSize();<a name="line.305"></a>
+<span class="sourceLineNo">306</span> }<a name="line.306"></a>
+<span class="sourceLineNo">307</span> long age = (this.now - cb.getCachedTime())/NANOS_PER_SECOND;<a name="line.307"></a>
+<span class="sourceLineNo">308</span> this.hist.add(age, 1);<a name="line.308"></a>
+<span class="sourceLineNo">309</span> return false;<a name="line.309"></a>
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+<span class="sourceLineNo">311</span><a name="line.311"></a>
+<span class="sourceLineNo">312</span> /**<a name="line.312"></a>
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+<span class="sourceLineNo">320</span><a name="line.320"></a>
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+<span class="sourceLineNo">324</span><a name="line.324"></a>
+<span class="sourceLineNo">325</span> /**<a name="line.325"></a>
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+<span class="sourceLineNo">330</span> }<a name="line.330"></a>
+<span class="sourceLineNo">331</span><a name="line.331"></a>
+<span class="sourceLineNo">332</span> public int getDataCount() {<a name="line.332"></a>
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+<span class="sourceLineNo">335</span><a name="line.335"></a>
+<span class="sourceLineNo">336</span> /**<a name="line.336"></a>
+<span class="sourceLineNo">337</span> * @return size of blocks in the cache<a name="line.337"></a>
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+<span class="sourceLineNo">339</span> public long getSize() {<a name="line.339"></a>
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+<span class="sourceLineNo">341</span> }<a name="line.341"></a>
+<span class="sourceLineNo">342</span><a name="line.342"></a>
+<span class="sourceLineNo">343</span> /**<a name="line.343"></a>
+<span class="sourceLineNo">344</span> * @return Size of data.<a name="line.344"></a>
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+<span class="sourceLineNo">346</span> public long getDataSize() {<a name="line.346"></a>
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+<span class="sourceLineNo">348</span> }<a name="line.348"></a>
+<span class="sourceLineNo">349</span><a name="line.349"></a>
+<span class="sourceLineNo">350</span> public AgeSnapshot getAgeInCacheSnapshot() {<a name="line.350"></a>
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+<span class="sourceLineNo">352</span> }<a name="line.352"></a>
+<span class="sourceLineNo">353</span><a name="line.353"></a>
+<span class="sourceLineNo">354</span> @Override<a name="line.354"></a>
+<span class="sourceLineNo">355</span> public String toString() {<a name="line.355"></a>
+<span class="sourceLineNo">356</span> AgeSnapshot snapshot = getAgeInCacheSnapshot();<a name="line.356"></a>
+<span class="sourceLineNo">357</span> return "count=" + count + ", dataBlockCount=" + dataBlockCount + ", size=" + size +<a name="line.357"></a>
+<span class="sourceLineNo">358</span> ", dataSize=" + getDataSize() +<a name="line.358"></a>
+<span class="sourceLineNo">359</span> ", mean age=" + snapshot.getMean() +<a name="line.359"></a>
+<span class="sourceLineNo">360</span> ", min age=" + snapshot.getMin() +<a name="line.360"></a>
+<span class="sourceLineNo">361</span> ", max age=" + snapshot.getMax() +<a name="line.361"></a>
+<span class="sourceLineNo">362</span> ", 75th percentile age=" + snapshot.get75thPercentile() +<a name="line.362"></a>
+<span class="sourceLineNo">363</span> ", 95th percentile age=" + snapshot.get95thPercentile() +<a name="line.363"></a>
+<span class="sourceLineNo">364</span> ", 98th percentile age=" + snapshot.get98thPercentile() +<a name="line.364"></a>
+<span class="sourceLineNo">365</span> ", 99th percentile age=" + snapshot.get99thPercentile() +<a name="line.365"></a>
+<span class="sourceLineNo">366</span> ", 99.9th percentile age=" + snapshot.get99thPercentile();<a name="line.366"></a>
+<span class="sourceLineNo">367</span> }<a name="line.367"></a>
+<span class="sourceLineNo">368</span> }<a name="line.368"></a>
+<span class="sourceLineNo">369</span>}<a name="line.369"></a>