Re: Bug: Buffer cache is not scan resistant - Mailing list pgsql-hackers

From Mark Kirkwood
Subject Re: Bug: Buffer cache is not scan resistant
Date
Msg-id 45EC94B7.3080303@paradise.net.nz
Whole thread Raw
In response to Re: Bug: Buffer cache is not scan resistant  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Bug: Buffer cache is not scan resistant  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Tom Lane wrote:

> 
> Hm, not really a smoking gun there.  But just for grins, would you try
> this patch and see if the numbers change?
> 

Applied to 8.2.3 (don't have lineitem loaded in HEAD yet) - no change 
that I can see:

procs -----------memory---------- ---swap-- -----io---- --system-- 
----cpu---- r  b   swpd   free   buff  cache   si   so    bi    bo   in    cs us 
sy id wa 1  0    764  55300      0 1988032    0    0 118797    32 1532  1775 15 
39 44  2 1  0    764  54476      0 1989720    0    0 115507     9 1456  3970 15 
39 45  1 1  0    788  54540      0 1989592    0    0 121651     0 1508  3221 16 
37 47  0 1  0    788  52808      0 1991320    0    0 124109     0 1532  1236 15 
38 46  0 1  0    788  52504      0 1991784    0    0 124518     0 1547  1005 16 
39 45  0 2  0    788  54544      0 1989740    0    5 117965     5 1491  2012 15 
36 47  2 1  0    788  53596      0 1991184    0    0 120424     0 1504  1910 16 
37 46  1

Elapsed time is exactly the same (101 s). Is is expected that HEAD would 
behave differently?

Cheers

Mark


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