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From Sylvain Lebresne <sylv...@datastax.com>
Subject Re: Lots of replicate on write tasks pending, want to investigate
Date Thu, 04 Jul 2013 06:29:02 GMT
> The write path (not replicate on write) for counters involves a read,
>

I'm afraid you got it wrong. The read done during counter writes *is* done
by the replicate on write taks. Though really, the replicate on write taks
are just one part of the counter write path (they are not "not the write
path").

--
Sylvain


>
> On Wed, Jul 3, 2013 at 1:03 PM, Robert Coli <rcoli@eventbrite.com> wrote:
>
>> On Wed, Jul 3, 2013 at 9:59 AM, Andrew Bialecki <
>> andrew.bialecki@gmail.com> wrote:
>>
>>> 2. I'm assuming in our case the cause is incrementing counters because
>>> disk reads are part of the write path for counters and are not for
>>> appending columns to a row. Does that logic make sense?
>>>
>>
>> That's a pretty reasonable assumption if you are not doing any other
>> reads and you see your disk busy doing non-compaction related reads. :)
>>
>> =Rob
>>
>
>

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