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https://issues.apache.org/jira/browse/HBASE-14177?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14903455#comment-14903455
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Nick Dimiduk commented on HBASE-14177:
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I missed your meaning here [~stack]. Is there nothing to fix in 0.98 at least?
FYI [~apurtell]
> Full GC on client may lead to missing scan results
> --------------------------------------------------
>
> Key: HBASE-14177
> URL: https://issues.apache.org/jira/browse/HBASE-14177
> Project: HBase
> Issue Type: Bug
> Components: Client
> Affects Versions: 1.1.0, 0.98.12, 0.98.13
> Reporter: James Estes
> Priority: Critical
> Labels: dataloss
> Fix For: 2.0.0, 1.3.0
>
>
> After adding a large row, scanning back that row winds up being empty. After
> a few attempts it will succeed (all attempts over the same data on an hbase
> getting no other writes).
> Looking at logs, it seems this happens when there is memory pressure on the
> client and there are several Full GCs that happen. Then messages that
> indicate that region locations are being removed from the local client cache:
> 2015-07-31 12:50:24,647 [main] DEBUG
> org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation
> - Removed 192.168.1.131:50981 as a location of
> big_row_1438368609944,,1438368610048.880c849594807bdc7412f4f982337d6c. for
> tableName=big_row_1438368609944 from cache
> Blaming the GC may sound fanciful, but if the test is run with -Xms4g -Xmx4g
> then it always passes on the first scan attempt. Maybe the pause is enough to
> remove something from the cache, or the client is using weak references
> somewhere?
> More info
> http://mail-archives.apache.org/mod_mbox/hbase-user/201507.mbox/%3CCAE8tVdnFf%3Dob569%3DfJkpw1ndVWOVTkihYj9eo6qt0FrzihYHgw%40mail.gmail.com%3E
> Test used to reproduce:
> https://github.com/housejester/hbase-debugging#fullgctest
> I tested and had failures in:
> 0.98.12 client/server
> 0.98.13 client 0.98.12 server
> 0.98.13 client/server
> 1.1.0 client 0.98.13 server
> 0.98.13 client and 1.1.0 server
> 0.98.12 client and 1.1.0 server
> I tested without failure in:
> 1.1.0 client/server
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