[asterixdb] branch master updated: [ASTERIXDB-2730][STO] Do not wait on flushing metadata indexes

[lu...@apache.org]

This is an automated email from the ASF dual-hosted git repository.

luochen pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/asterixdb.git


The following commit(s) were added to refs/heads/master by this push:
     new d6f10a8  [ASTERIXDB-2730][STO] Do not wait on flushing metadata indexes
d6f10a8 is described below

commit d6f10a8c82ce6dc9bc37d6d708c64b3f90d8dc31
Author: luochen <cl...@uci.edu>
AuthorDate: Sun May 17 21:14:37 2020 -0700

    [ASTERIXDB-2730][STO] Do not wait on flushing metadata indexes
    
    - user model changes: no
    - storage format changes: no
    - interface changes: no
    
    Details:
    - Ensure GVBC does not wait on flushing metadata indexes because
    metadata indexes support full ACID transactions and waiting on them
    can lead to deadlocks.
    - Add more log messages to GVBC.
    
    Change-Id: Iba4020d8584768940176023ac4ab9135cff7b7e6
    Reviewed-on: https://asterix-gerrit.ics.uci.edu/c/asterixdb/+/6345
    Integration-Tests: Jenkins <je...@fulliautomatix.ics.uci.edu>
    Tested-by: Jenkins <je...@fulliautomatix.ics.uci.edu>
    Reviewed-by: Murtadha Hubail <mh...@apache.org>
---
 .../common/context/GlobalVirtualBufferCache.java   | 29 +++++++++++++++++++++-
 1 file changed, 28 insertions(+), 1 deletion(-)

diff --git a/asterixdb/asterix-common/src/main/java/org/apache/asterix/common/context/GlobalVirtualBufferCache.java b/asterixdb/asterix-common/src/main/java/org/apache/asterix/common/context/GlobalVirtualBufferCache.java
index c0197b0..e3bd13d 100644
--- a/asterixdb/asterix-common/src/main/java/org/apache/asterix/common/context/GlobalVirtualBufferCache.java
+++ b/asterixdb/asterix-common/src/main/java/org/apache/asterix/common/context/GlobalVirtualBufferCache.java
@@ -29,6 +29,7 @@ import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
 
 import org.apache.asterix.common.config.StorageProperties;
+import org.apache.asterix.common.metadata.MetadataIndexImmutableProperties;
 import org.apache.hyracks.api.exceptions.HyracksDataException;
 import org.apache.hyracks.api.io.FileReference;
 import org.apache.hyracks.api.lifecycle.ILifeCycleComponent;
@@ -102,6 +103,10 @@ public class GlobalVirtualBufferCache implements IVirtualBufferCache, ILifeCycle
             if (!primaryIndexes.contains(index)) {
                 // make sure only add index once
                 primaryIndexes.add(index);
+                if (LOGGER.isInfoEnabled()) {
+                    LOGGER.info("Registered {} index {} to the global VBC",
+                            isMetadataIndex(index) ? "metadata" : "primary", index.toString());
+                }
             }
             if (index.getNumOfFilterFields() > 0) {
                 // handle filtered primary index
@@ -123,6 +128,10 @@ public class GlobalVirtualBufferCache implements IVirtualBufferCache, ILifeCycle
             int pos = primaryIndexes.indexOf(index);
             if (pos >= 0) {
                 primaryIndexes.remove(index);
+                if (LOGGER.isInfoEnabled()) {
+                    LOGGER.info("Unregistered {} index {} to the global VBC",
+                            isMetadataIndex(index) ? "metadata" : "primary", index.toString());
+                }
                 if (primaryIndexes.isEmpty()) {
                     flushPtr = 0;
                 } else if (flushPtr > pos) {
@@ -160,6 +169,11 @@ public class GlobalVirtualBufferCache implements IVirtualBufferCache, ILifeCycle
                             opTracker.notifyAll();
                         }
                     }
+
+                    if (LOGGER.isInfoEnabled()) {
+                        LOGGER.info("Completed flushing {}. Resetting flushIndex back to null.",
+                                memoryComponent.getIndex().toString());
+                    }
                 }
             }
             checkAndNotifyFlushThread();
@@ -421,6 +435,11 @@ public class GlobalVirtualBufferCache implements IVirtualBufferCache, ILifeCycle
         return vbc.getUsage();
     }
 
+    private boolean isMetadataIndex(ILSMIndex index) {
+        BaseOperationTracker opTracker = (BaseOperationTracker) index.getOperationTracker();
+        return MetadataIndexImmutableProperties.isMetadataDataset(opTracker.getDatasetInfo().getDatasetID());
+    }
+
     /**
      * We use a dedicated thread to schedule flushes to avoid deadlock. We cannot schedule flushes directly during
      * page pins because page pins can be called while synchronized on op trackers (e.g., when resetting a
@@ -476,9 +495,17 @@ public class GlobalVirtualBufferCache implements IVirtualBufferCache, ILifeCycle
                             opTracker.flushIfNeeded();
                             // If the flush cannot be scheduled at this time, then there must be active writers.
                             // The flush will be eventually scheduled when writers exit
+                            if (LOGGER.isInfoEnabled()) {
+                                LOGGER.info("Requested {} flushing primary index {}",
+                                        isMetadataIndex(primaryIndex) ? "metadata" : "primary",
+                                        primaryIndex.toString());
+                            }
                         }
-                        if (flushable || opTracker.isFlushLogCreated()) {
+                        if ((flushable || opTracker.isFlushLogCreated()) && !isMetadataIndex(primaryIndex)) {
+                            // global vbc cannot wait on metadata indexes because metadata indexes support full
+                            // ACID transactions. Waiting on metadata indexes can introduce deadlocks.
                             flushingIndex = primaryIndex;
+                            LOGGER.debug("Waiting for flushing primary index {} to complete...", primaryIndex);
                             break;
                         }
                     }