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https://issues.apache.org/jira/browse/HBASE-3777?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13026056#comment-13026056
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jirapos...@reviews.apache.org commented on HBASE-3777:
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This is an automatically generated e-mail. To reply, visit:
https://reviews.apache.org/r/643/
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(Updated 2011-04-28 00:13:52.902673)
Review request for hbase and Ted Yu.
Changes
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The V7 version of the patch make the following additional changes:
a) Adds a HCM#execute method for executing blocks that require short-lived
connections.
b) Removes the HCM#deleteConnection from the HMaster and HRegionServer classes,
as they no longer directly get connections.
c) Adds a connection field in the ServerManager class, which is gotten in its
constructor and deleted when it's stopped.
All but two tests (viz., TestSplitLogWorker and TestCatalogJanitor) passed.
FWIW, those two failures happen without the patch as well, and only if the
"hbase.master.distributed.log.splitting" is true.
PS: Just heard from Ted Yu that Stack checked in a patch for HBASE-1502, which
I'll rebase with and test tomorrow. In the meantime, please review the three
critical changes described above.
Summary
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Judging from the javadoc in HConnectionManager, sharing connections across
multiple clients going to the same cluster is supposedly a good thing. However,
the fact that there is a one-to-one mapping between a configuration and
connection instance, kind of works against that goal. Specifically, when you
create HTable instances using a given Configuration instance and a copy
thereof, we end up with two distinct HConnection instances under the covers. Is
this really expected behavior, especially given that the configuration instance
gets cloned a lot?
Here, I'd like to play devil's advocate and propose that we "deep-compare"
HBaseConfiguration instances, so that multiple HBaseConfiguration instances
that have the same properties map to the same HConnection instance. In case one
is "concerned that a single HConnection is insufficient for sharing amongst
clients", to quote the javadoc, then one should be able to mark a given
HBaseConfiguration instance as being "uniquely identifiable".
This addresses bug HBASE-3777.
https://issues.apache.org/jira/browse/HBASE-3777
Diffs (updated)
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src/main/java/org/apache/hadoop/hbase/HConstants.java 5701639
src/main/java/org/apache/hadoop/hbase/catalog/CatalogTracker.java be31179
src/main/java/org/apache/hadoop/hbase/client/HBaseAdmin.java afb666a
src/main/java/org/apache/hadoop/hbase/client/HConnectionManager.java 70affa0
src/main/java/org/apache/hadoop/hbase/client/HTable.java edacf56
src/main/java/org/apache/hadoop/hbase/client/HTablePool.java 88827a8
src/main/java/org/apache/hadoop/hbase/client/MetaScanner.java 9e3f4d1
src/main/java/org/apache/hadoop/hbase/client/replication/ReplicationAdmin.java
d76e333
src/main/java/org/apache/hadoop/hbase/mapred/TableOutputFormat.java 80284bb
src/main/java/org/apache/hadoop/hbase/mapreduce/TableOutputFormat.java
05d9395
src/main/java/org/apache/hadoop/hbase/mapreduce/replication/VerifyReplication.java
ed88bfa
src/main/java/org/apache/hadoop/hbase/master/HMaster.java 250a8cf
src/main/java/org/apache/hadoop/hbase/master/ServerManager.java 04befe9
src/main/java/org/apache/hadoop/hbase/regionserver/HRegionServer.java d0a1e11
src/main/java/org/apache/hadoop/hbase/replication/regionserver/ReplicationSource.java
78c3b42
src/main/java/org/apache/hadoop/hbase/util/HBaseFsck.java 5da5e34
src/main/java/org/apache/hadoop/hbase/util/HBaseFsckRepair.java b624d28
src/main/java/org/apache/hadoop/hbase/zookeeper/ZKUtil.java 7f5b377
src/main/java/org/apache/hadoop/hbase/zookeeper/ZooKeeperWatcher.java dc471c4
src/test/java/org/apache/hadoop/hbase/catalog/TestCatalogTracker.java e25184e
src/test/java/org/apache/hadoop/hbase/catalog/TestMetaReaderEditor.java
60320a3
src/test/java/org/apache/hadoop/hbase/client/TestHCM.java b01a2d2
src/test/java/org/apache/hadoop/hbase/mapreduce/TestTableMapReduce.java
624f4a8
src/test/java/org/apache/hadoop/hbase/master/TestClockSkewDetection.java
915cdf6
src/test/java/org/apache/hadoop/hbase/util/TestMergeTable.java 8992dbb
Diff: https://reviews.apache.org/r/643/diff
Testing
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mvn test
Thanks,
Karthick
> Redefine Identity Of HBase Configuration
> ----------------------------------------
>
> Key: HBASE-3777
> URL: https://issues.apache.org/jira/browse/HBASE-3777
> Project: HBase
> Issue Type: Improvement
> Components: client, ipc
> Affects Versions: 0.90.2
> Reporter: Karthick Sankarachary
> Assignee: Karthick Sankarachary
> Priority: Minor
> Fix For: 0.92.0
>
> Attachments: 3777-TOF.patch, HBASE-3777-V2.patch,
> HBASE-3777-V3.patch, HBASE-3777-V4.patch, HBASE-3777-V6.patch,
> HBASE-3777.patch
>
>
> Judging from the javadoc in {{HConnectionManager}}, sharing connections
> across multiple clients going to the same cluster is supposedly a good thing.
> However, the fact that there is a one-to-one mapping between a configuration
> and connection instance, kind of works against that goal. Specifically, when
> you create {{HTable}} instances using a given {{Configuration}} instance and
> a copy thereof, we end up with two distinct {{HConnection}} instances under
> the covers. Is this really expected behavior, especially given that the
> configuration instance gets cloned a lot?
> Here, I'd like to play devil's advocate and propose that we "deep-compare"
> {{HBaseConfiguration}} instances, so that multiple {{HBaseConfiguration}}
> instances that have the same properties map to the same {{HConnection}}
> instance. In case one is "concerned that a single {{HConnection}} is
> insufficient for sharing amongst clients", to quote the javadoc, then one
> should be able to mark a given {{HBaseConfiguration}} instance as being
> "uniquely identifiable".
> Note that "sharing connections makes clean up of {{HConnection}} instances a
> little awkward", unless of course, you apply the change described in
> HBASE-3766.
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