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Date: Mon, 05 Sep 2011 22:06:30 +0100
From: Bill <bill@dehora.net>
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Subject: Re: [DISCUSSION] Accumulo, another BigTable clone, has shown up on
 Apache Incubator as a proposal
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On 04/09/11 07:43, Mathias Herberts wrote:
> On Sep 4, 2011 1:39 AM, "Bill de hÓra"<lists@dehora.net>  wrote:
>>
>> On 02/09/11 19:06, Stack wrote:
>>>
>>> What do folks think?
>>
>>
>> Not putting the log into hdfs seems like a good idea.
>
> I was somehow thinking the opposite as it makes irrecoverable machine
> failures much more problematic. What makes you say it's a good idea?
>

Allows more control over the write path, specifically sequential I/O and 
crash recovery. Granted the commit needs to be replicated, but you need 
that regardless. Thinking a bit more it might not square with the 
regionserver model anyway, plus the Accumulo proposal mentions a service 
rather than a local disk. The WAL seems to be hardened up these days 
anyway making things like 
https://issues.apache.org/jira/browse/HBASE-4107 more of an edge case..

Bill