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Date: Wed, 02 May 2012 16:10:26 +0200
From: Mikael Wikblom <mikael.wikblom@sitevision.se>
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To: user@cassandra.apache.org
Subject: Re: Memtable.flushAndSignal "hangs"
 ColumnFamilyStore.maybeSwitchMemtable
 on IOException
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	<4F912F85.2050404@opera.com>	<4FA12BC5.2090101@sitevision.se>
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ok, just find it a bit hard to be forced to shutdown the node in case of 
an IOException, but I understand why. The exception occurred because of 
a missing native snappy library on the server, but the error only occur 
because we initialized a column family incorrectly (we are using 
cassandra embedded and are working directly against the internal APIs).

Regards
Mikael Wikblom


On 05/02/2012 03:03 PM, Sylvain Lebresne wrote:
> On Wed, May 2, 2012 at 2:42 PM, Mikael Wikblom
> <mikael.wikblom@sitevision.se>  wrote:
>> Given an IOException in writeSortedContents the latch.countDown() will not
>> be called. Wouldn't it be better to place the latch.countDown() in the
>> finally statement?
> No because having the latch being countDown means 'the sstable has
> been flushed successfully and the data can be safely deleted in the
> commit log', which is not the case if you get an IOException.
>
>> We've had issues with IOExceptions in writeSortedContents when doing a snapshot which hung a thread (and still hangs) for 4 days.
> It would be interesting to know what triggered the IOException. If
> that's due to a bug, then that's the one we should fix in priority. If
> that's you running out of disk-space or something like that, you
> should probably fix that and restart C*.
>
> --
> Sylvain


-- 
Mikael Wikblom
Software Architect
SiteVision AB
019-217058
mikael.wikblom@sitevision.se
http://www.sitevision.se