Re: Speed up Clog Access by increasing CLOG buffers

On 10/08/2016 07:47 AM, Amit Kapila wrote:
> On Fri, Oct 7, 2016 at 3:02 PM, Tomas Vondra
> <tomas(dot)vondra(at)2ndquadrant(dot)com> wrote:
>
> ...
>
>> In total, I plan to test combinations of:
>>
>> (a) Dilip's workload and pgbench (regular and -N)
>> (b) logged and unlogged tables
>> (c) scale 300 and scale 3000 (both fits into RAM)
>> (d) sync_commit=on/off
>>
>
> sounds sensible.
>
> Thanks for doing the tests.
>

FWIW I've started those tests on the big machine provided by Oleg and
Alexander, an estimate to complete all the benchmarks is 9 days. The
results will be pushed

to https://bitbucket.org/tvondra/hp05-results/src

after testing each combination (every ~9 hours). Inspired by Robert's
wait event post a few days ago, I've added wait event sampling so that
we can perform similar analysis. (Neat idea!)

While messing with the kernel on the other machine I've managed to
misconfigure it to the extent that it's not accessible anymore. I'll
start similar benchmarks once I find someone with console access who can
fix the boot.

regards

--
Tomas Vondra http://www.2ndQuadrant.com
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