Re: CLOG contention

On Thu, Jan 5, 2012 at 4:04 PM, Robert Haas <robertmhaas@gmail.com> wrote:

> It appears to me that increasing the number of CLOG buffers reduced
> the severity of the latency spikes considerably.  In the last 100
> seconds, for example, master has several spikes in the 500-700ms
> range, but with 32 CLOG buffers it never goes above 400 ms.  Also, the
> number of points associated with each spike is considerably less -
> each spike seems to affect fewer transactions.  So it seems that at
> least on this machine, increasing the number of CLOG buffers both
> improves performance and reduces latency.

I believed before that the increase was worthwhile and now even more so.

Let's commit the change to 32.

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 Simon Riggs                   http://www.2ndQuadrant.com/
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