Re: [WIP] Double-write with Fast Checksums

On 01/17/2012 03:47 PM, Kevin Grittner wrote:
> I'm very curious about what impact DW would have on big servers with
> write-back cache that becomes saturated, like in Greg Smith's post
> here...

My guess is that a percentage of the dbt-2 run results posted here are 
hitting that sort of problem.  We just don't know which, because the 
results numbers posted were all the throughput numbers.  I haven't 
figure out a way to look for cache saturation issues other than 
collecting all the latency information for each transaction, then 
graphing that out if the worst-case value is poor.  It's quite possible 
they have that data but just didn't post just to keep the summary size 
managable, since dbt-2 collects a lot of information.

-- 
Greg Smith   2ndQuadrant US    greg@2ndQuadrant.com   Baltimore, MD
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