[infinispan-issues] [JBoss JIRA] (ISPN-3366) Data loss when entry forwarding to primary owner and primary owner shutdown

[Dan Berindei (JIRA)]

    [ https://issues.jboss.org/browse/ISPN-3366?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12795115#comment-12795115 ] 

Dan Berindei commented on ISPN-3366:
------------------------------------

Looks like the remaining data loss has a slightly different cause: a node can become primary owner while a command is executing. 

So we could have {{isPrimaryOwner(k) == false}} in EntryWrappingInterceptor, and {{isPrimaryOwner(k) == true}} by the time we enter NonTx[Concurrent]DistributionInterceptor:

{noformat}
11:23:12,876 TRACE [NonTransactionalLockingInterceptor] (HotRodServerWorker-9) Are (node2/clustered(s1)) we the lock owners for key 'ByteArrayKey{data=ByteArray{size=16, hashCode=4d12e1a9, array=0x033e0d74687265616431306b65793539}}'? false
11:23:12,876 TRACE [EntryWrappingInterceptor] (HotRodServerWorker-9) Wrapping entry 'ByteArrayKey{data=ByteArray{size=16, hashCode=4d12e1a9, array=0x033e0d74687265616431306b65793539}}'? false
11:23:12,882 TRACE [NonTxDistributionInterceptor] (HotRodServerWorker-9) Not doing a remote get for key ByteArrayKey{data=ByteArray{size=16, hashCode=4d12e1a9, array=0x033e0d74687265616431306b65793539}} since entry is not affected by rehash or is already in data container. We are node2/clustered(s1), owners are [node4/clustered(s1), node2/clustered(s1)]
11:23:12,886 TRACE [NonTxConcurrentDistributionInterceptor] (HotRodServerWorker-9) I'm the primary owner, sending the command to all ([node2/clustered(s1)]) the recipients in order to be applied.
{noformat}

Because the key is not wrapped on the originator, it's not written to the data container, but the command isn't looped back to the originator from the primary owner either.

A possible solution would be to check the topology id of the command against the current topology id before sending it, and throw an OutdatedTopologyException to cause StateTransferInterceptor to retry the command.

                
> Data loss when entry forwarding to primary owner and primary owner shutdown
> ---------------------------------------------------------------------------
>
>                 Key: ISPN-3366
>                 URL: https://issues.jboss.org/browse/ISPN-3366
>             Project: Infinispan
>          Issue Type: Bug
>          Components: Distributed Cache
>    Affects Versions: 5.2.4.Final, 6.0.0.Alpha1
>            Reporter: Takayoshi Kimura
>            Assignee: Dan Berindei
>            Priority: Critical
>             Fix For: 5.2.8.Final, 6.0.0.Alpha3, 6.0.0.Final
>
>         Attachments: ISPN-3366-full-logs-3rd.zip, ISPN-3366-logs.zip
>
>
>   Looks like a problem in entry forwarding.
> Here is test scenario:
> * DIST numOwners=2, start with 4 nodes cluster then normal shutdown 1 node during load
> * HotRod putIfAbsent accesses from 40 threads (1 process, 1 remote cache instance), 40000 entries total
> After the test run, the numberOfEntries on each node are:
> * node1: 26608
> * node2: 26622
> * node3: 26746
> * node4: 0
> Total is 79976 and HotRod client received 11 errors, so 79976 + (11 * 2) = 79998. It means 1 entry is completely missing.
> Let's take a look at the missing entry, hash(thread16key59) = 574ff563.
> Current CH: owners(574ff563) are [node4, node1]
> The events sequence is:
> * hotrod -> node1
> * node1 forwarding it to primary owner node4
> * node4 doesn't process the forwarded entry, shutdown
> Result owners(7c29bccb) is [] empty. This entry is completely lost without any errors.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira