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From Stack <st...@duboce.net>
Subject Re: Help regarding RowLock
Date Fri, 30 Dec 2011 04:47:37 GMT
On Thu, Dec 29, 2011 at 8:50 AM, lars hofhansl <lhofhansl@yahoo.com> wrote:
> Well... Uhm... That is actually not entirely true. For performance these operations modify
the MemStore, then release the row lock,
> then write the relevant entries to the WAL (to avoid holding the row lock while the WAL
is written).
> So what could theoretically happen is that writing the WAL fails (because some issue
with HDFS).
> Now say some other clients read the changes in the MemStore and then the RegionServer
dies before it could flush the MemStore.
> Now you have clients that have read transient data. However, if HDFS has a problem, you
have bigger problems anyway.

I opened an issue to make it so we do the 'correct' behavior first,
and then, optionally do as described above:

Good on you Lars,

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