Re: sudden spurt in swap utilization (was:cpu bound postgresql setup.) - Mailing list pgsql-performance

From Rajesh Kumar Mallah
Subject Re: sudden spurt in swap utilization (was:cpu bound postgresql setup.)
Date
Msg-id AANLkTimPhkr2nvuLo-fpBfUdN08KsDFTwzL9ubJP5VG2@mail.gmail.com
Whole thread Raw
In response to Re: sudden spurt in swap utilization (was:cpu bound postgresql setup.)  ("Kevin Grittner" <Kevin.Grittner@wicourts.gov>)
Responses Re: sudden spurt in swap utilization (was:cpu bound postgresql setup.)  (Rajesh Kumar Mallah <mallah.rajesh@gmail.com>)
List pgsql-performance
I changed shared_buffers from 10G to 4G ,
swap usage has almost become nil.

# free
             total       used       free     shared    buffers     cached
Mem:      32871276   24575824    8295452          0      11064   22167324
-/+ buffers/cache:    2397436   30473840
Swap:      4192912        352    4192560

I also observed that there was a huge IO wait and load spike initially
which gradually reduced to normal levels. Now things seems to be
fine. but real test shall be during business hours.

vmstat output:
http://pastebin.com/ygu8gUhS

the iowait now is very respectable < 10% and CPU is idling most of
the time.

# vmstat 10
procs -----------memory---------- ---swap-- -----io---- --system--
-----cpu------
 r  b   swpd   free   buff  cache   si   so    bi    bo   in   cs us sy id wa st
 2  1    352 8482444  11336 22299100    1    0   450   208    0    0
50  6 39  5  0
 4  0    352 8393840  11352 22304484    0    0   480   163 9260 12717
32  4 62  3  0
 5  1    352 8474788  11360 22308980    0    0   304   445 8295 12358
28  4 67  2  0
 3  0    352 8370672  11376 22316676    0    0   648   158 8760 13214
38  4 55  3  0
11  0    352 8193824  11392 22323572    0    0   621   577 8800 13163
37  4 56  3  0
 2  0    352 8229012  11408 22326664    0    0   169   405 9588 13696
34  4 61  1  0
 6  1    352 8319176  11424 22333144    0    0   559   170 8830 12929
32  4 61  3  0

I shall also try pgtune in a while.

pgsql-performance by date:

Previous
From: Tom Lane
Date:
Subject: Re: Occasional giant spikes in CPU load
Next
From: Rajesh Kumar Mallah
Date:
Subject: Re: sudden spurt in swap utilization (was:cpu bound postgresql setup.)