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(at)2ndQuadrant(dot)com Baltimore, MD
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