Re: SMP on a heavy loaded database

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Thu, Jan 3, 2013 at 4:45 PM, nobody nowhere <devnull@xxxxxxx> wrote:
> Centos 5.X kernel 2.6.18-274
> pgsql-9.1 from pgdg-91-centos.repo
> relatively small database 3.2Gb
> Lot of insert, update, delete.
>
> I see non balanced _User_ usage on 14 CPU, exclusively assigned to the hardware raid controller.
> What I'm doing wrong, and is it possible somehow to fix?
>
> Thanks in advance.
>
> Andrew.
>
> # top -d 10.00 -b -n 2 -U postgres -c
>
> top - 23:18:19 up 453 days, 57 min,  3 users,  load average: 0.55, 0.47, 0.42
> Tasks: 453 total,   1 running, 452 sleeping,   0 stopped,   0 zombie
> Cpu0  :  0.6%us,  0.1%sy,  0.0%ni, 99.3%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
> Cpu1  :  0.0%us,  0.0%sy,  0.0%ni,100.0%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
> Cpu2  :  0.0%us,  0.0%sy,  0.0%ni,100.0%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
> Cpu3  :  1.2%us,  0.1%sy,  0.0%ni, 98.7%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
> Cpu4  :  2.6%us,  0.4%sy,  0.0%ni, 96.8%id,  0.0%wa,  0.0%hi,  0.2%si,  0.0%st
> Cpu5  :  0.8%us,  0.0%sy,  0.0%ni, 99.2%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
> Cpu6  :  5.4%us,  0.2%sy,  0.0%ni, 94.2%id,  0.2%wa,  0.0%hi,  0.0%si,  0.0%st
> Cpu7  :  3.3%us,  0.4%sy,  0.0%ni, 96.1%id,  0.0%wa,  0.0%hi,  0.2%si,  0.0%st
> Cpu8  :  1.4%us,  0.3%sy,  0.0%ni, 98.2%id,  0.0%wa,  0.0%hi,  0.1%si,  0.0%st
> Cpu9  :  0.0%us,  0.1%sy,  0.0%ni, 99.9%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
> Cpu10 :  0.0%us,  0.1%sy,  0.0%ni, 99.9%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
> Cpu11 :  1.6%us,  0.6%sy,  0.0%ni, 97.4%id,  0.0%wa,  0.0%hi,  0.4%si,  0.0%st
> Cpu12 :  0.5%us,  0.1%sy,  0.0%ni, 99.4%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
> Cpu13 :  1.4%us,  0.2%sy,  0.0%ni, 98.4%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st
> Cpu14 : 24.2%us,  0.8%sy,  0.0%ni, 74.5%id,  0.3%wa,  0.0%hi,  0.2%si,  0.0%st
> Cpu15 :  0.7%us,  0.1%sy,  0.0%ni, 99.0%id,  0.0%wa,  0.1%hi,  0.1%si,  0.0%st
> Mem:  16426540k total, 16356772k used,    69768k free,   215764k buffers
> Swap:  4194232k total,   145280k used,  4048952k free, 14434356k cached
>

So how many concurrent users are accessing this db?  pgsql assigns one
process on one core so to speak.  It can't spread load for one user
over all cores.


-- 
Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-performance


[Postgresql General]     [Postgresql PHP]     [PHP Users]     [PHP Home]     [PHP on Windows]     [Kernel Newbies]     [PHP Classes]     [PHP Books]     [PHP Databases]     [Yosemite]

  Powered by Linux