Thread: Postmaster only takes 4-5% CPU

Postmaster only takes 4-5% CPU

From
Ruben
Date:
Hi all:

When I run a (big) query from pgsql, postmaster used to take almost 100%
of CPU. Now, with aparent no reason, Postmaster only takes 4-5% CPU and
the same query takes really longer to finish.

I have tried renicing -20 postmaster but it still only takes a small
percentage of CPU, while 90% is idle.

This is a "top" screen while running the query:

   2:27pm  up 5 min,  2 users,  load average: 0,80, 0,26, 0,08
74 processes: 72 sleeping, 2 running, 0 zombie, 0 stopped
CPU states:  3,1% user,  2,1% system,  0,0% nice, 94,6% idle
Mem:  1031012K av,  246040K used,  784972K free,       0K shrd,   11496K
buff
Swap: 2040244K av,       0K used, 2040244K free                  196916K
cached

   PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM   TIME COMMAND
  1165 postgres   0 -20  3476 3476  2912 D <   4,5  0,3   0:02 postmaster
   268 root      15   0     0    0     0 SW    0,1  0,0   0:00 kjournald

Any idea of how can I get postmaster to eat as much CPU as possible?

Thanks a lot! Ruben.


Re: Postmaster only takes 4-5% CPU

From
Jan Poslusny
Date:
Did not your postmaster wait for harddisk ?

Ruben wrote:
> Hi all:
>
> When I run a (big) query from pgsql, postmaster used to take almost 100%
> of CPU. Now, with aparent no reason, Postmaster only takes 4-5% CPU and
> the same query takes really longer to finish.
>
> I have tried renicing -20 postmaster but it still only takes a small
> percentage of CPU, while 90% is idle.
>
> This is a "top" screen while running the query:
>
>   2:27pm  up 5 min,  2 users,  load average: 0,80, 0,26, 0,08
> 74 processes: 72 sleeping, 2 running, 0 zombie, 0 stopped
> CPU states:  3,1% user,  2,1% system,  0,0% nice, 94,6% idle
> Mem:  1031012K av,  246040K used,  784972K free,       0K shrd,   11496K
> buff
> Swap: 2040244K av,       0K used, 2040244K free                  196916K
> cached
>
>   PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM   TIME COMMAND
>  1165 postgres   0 -20  3476 3476  2912 D <   4,5  0,3   0:02 postmaster
>   268 root      15   0     0    0     0 SW    0,1  0,0   0:00 kjournald
>
> Any idea of how can I get postmaster to eat as much CPU as possible?
>
> Thanks a lot! Ruben.
>
>
> ---------------------------(end of broadcast)---------------------------
> TIP 4: Don't 'kill -9' the postmaster
>


Re: Postmaster only takes 4-5% CPU

From
Ruben
Date:
Hi Jan:

There is no disk activity to wait for.

Thanks.

Jan Poslusny wrote:
> Did not your postmaster wait for harddisk ?
>
> Ruben wrote:
>
>> Hi all:
>>
>> When I run a (big) query from pgsql, postmaster used to take almost
>> 100% of CPU. Now, with aparent no reason, Postmaster only takes 4-5%
>> CPU and the same query takes really longer to finish.
>>
>> I have tried renicing -20 postmaster but it still only takes a small
>> percentage of CPU, while 90% is idle.
>>
>> This is a "top" screen while running the query:
>>
>>   2:27pm  up 5 min,  2 users,  load average: 0,80, 0,26, 0,08
>> 74 processes: 72 sleeping, 2 running, 0 zombie, 0 stopped
>> CPU states:  3,1% user,  2,1% system,  0,0% nice, 94,6% idle
>> Mem:  1031012K av,  246040K used,  784972K free,       0K shrd,
>> 11496K buff
>> Swap: 2040244K av,       0K used, 2040244K free
>> 196916K cached
>>
>>   PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM   TIME COMMAND
>>  1165 postgres   0 -20  3476 3476  2912 D <   4,5  0,3   0:02 postmaster
>>   268 root      15   0     0    0     0 SW    0,1  0,0   0:00 kjournald
>>
>> Any idea of how can I get postmaster to eat as much CPU as possible?
>>
>> Thanks a lot! Ruben.
>>
>>
>> ---------------------------(end of broadcast)---------------------------
>> TIP 4: Don't 'kill -9' the postmaster
>>
>


Re: Postmaster only takes 4-5% CPU

From
"Shridhar Daithankar"
Date:
On 29 May 2003 at 13:24, Ruben wrote:
> When I run a (big) query from pgsql, postmaster used to take almost 100%
> of CPU. Now, with aparent no reason, Postmaster only takes 4-5% CPU and
> the same query takes really longer to finish.

Check vmstat when query is running. Is it saturating disk BW? If yes, have you
vacuummed the table/database recently?

HTH
Bye
 Shridhar

--
Slurm, n.:    The slime that accumulates on the underside of a soap bar when    it
sits in the dish too long.        -- Rich Hall, "Sniglets"


Re: Postmaster only takes 4-5% CPU

From
Arjen van der Meijden
Date:
Since there is 2.1% system usage, kjournald has cpu-usage and postgres
has the status 'D' that's probably the case.

Arjen

> Jan Poslusny wrote:
>
> Did not your postmaster wait for harddisk ?
>
> Ruben wrote:
> > Hi all:
> >
> > When I run a (big) query from pgsql, postmaster used to take almost
> > 100%
> > of CPU. Now, with aparent no reason, Postmaster only takes
> 4-5% CPU and
> > the same query takes really longer to finish.
> >
> > I have tried renicing -20 postmaster but it still only takes a small
> > percentage of CPU, while 90% is idle.
> >
> > This is a "top" screen while running the query:
> >
> >   2:27pm  up 5 min,  2 users,  load average: 0,80, 0,26, 0,08 74
> > processes: 72 sleeping, 2 running, 0 zombie, 0 stopped CPU states:
> > 3,1% user,  2,1% system,  0,0% nice, 94,6% idle
> > Mem:  1031012K av,  246040K used,  784972K free,       0K
> shrd,   11496K
> > buff
> > Swap: 2040244K av,       0K used, 2040244K free
>      196916K
> > cached
> >
> >   PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM
> TIME COMMAND
> >  1165 postgres   0 -20  3476 3476  2912 D <   4,5  0,3
> 0:02 postmaster
> >   268 root      15   0     0    0     0 SW    0,1  0,0
> 0:00 kjournald
> >
> > Any idea of how can I get postmaster to eat as much CPU as possible?
> >
> > Thanks a lot! Ruben.
> >
> >
> > ---------------------------(end of
> > broadcast)---------------------------
> > TIP 4: Don't 'kill -9' the postmaster
> >
>
>
> ---------------------------(end of
> broadcast)---------------------------
> TIP 1: subscribe and unsubscribe commands go to
> majordomo@postgresql.org
>



Re: Postmaster only takes 4-5% CPU

From
"scott.marlowe"
Date:
On Thu, 29 May 2003, Ruben wrote:

> Hi all:
>
> When I run a (big) query from pgsql, postmaster used to take almost 100%
> of CPU. Now, with aparent no reason, Postmaster only takes 4-5% CPU and
> the same query takes really longer to finish.
>
> I have tried renicing -20 postmaster but it still only takes a small
> percentage of CPU, while 90% is idle.
>
> This is a "top" screen while running the query:
>
>    2:27pm  up 5 min,  2 users,  load average: 0,80, 0,26, 0,08
> 74 processes: 72 sleeping, 2 running, 0 zombie, 0 stopped
> CPU states:  3,1% user,  2,1% system,  0,0% nice, 94,6% idle
> Mem:  1031012K av,  246040K used,  784972K free,       0K shrd,   11496K
> buff
> Swap: 2040244K av,       0K used, 2040244K free                  196916K
> cached
>
>    PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM   TIME COMMAND
>   1165 postgres   0 -20  3476 3476  2912 D <   4,5  0,3   0:02 postmaster
>    268 root      15   0     0    0     0 SW    0,1  0,0   0:00 kjournald
>
> Any idea of how can I get postmaster to eat as much CPU as possible?

Looks like you're waiting on I/O.  What's your disk subsystem
configuration?


Re: Postmaster only takes 4-5% CPU

From
Ruben
Date:
Thanks for your answers Jan, Arjen, Shridar and Scott:

Postmaster is back taking lots of CPU when needed. I guess you were
right about Postgres waiting for some I/O activity. Anyway, I was not
able to see what process was responsible for this, since top showed
nothing remarkable.

This is a new top while running a VACUUM of the database:

   8:51pm  up  6:30,  3 users,  load average: 0,45, 0,11, 0,04
93 processes: 89 sleeping, 4 running, 0 zombie, 0 stopped
CPU states:  0,1% user,  1,1% system,  0,0% nice, 98,6% idle
Mem:  1031012K av, 1019612K used,   11400K free,  0K shrd,   44896K buff
Swap: 2040244K av,    1716K used, 2038528K free          894008K cached

   PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM   TIME COMMAND
  1673 postgres  15   0  5120 5120  3196 R     0,9  0,4   0:02 postmaster
  1683 root      15   0  1044 1044   840 R     0,1  0,1   0:00 top
     1 root      15   0   476  476   424 S     0,0  0,0   0:04 init
     2 root      15   0     0    0     0 SW    0,0  0,0   0:00 keventd
     3 root      15   0     0    0     0 SW    0,0  0,0   0:00 kapmd
     4 root      34  19     0    0     0 SWN   0,0  0,0   0:00
ksoftirqd_CPU0
     5 root      15   0     0    0     0 SW    0,0  0,0   0:00 kswapd
     6 root      15   0     0    0     0 SW    0,0  0,0   0:00 bdflush
     7 root      15   0     0    0     0 SW    0,0  0,0   0:00 kupdated
     8 root      25   0     0    0     0 SW    0,0  0,0   0:00 mdrecoveryd
    12 root      15   0     0    0     0 SW    0,0  0,0   0:00 kjournald
    66 root      15   0     0    0     0 SW    0,0  0,0   0:00 khubd
   266 root      15   0     0    0     0 SW    0,0  0,0   0:00 kjournald
   267 root      15   0     0    0     0 SW    0,0  0,0   0:00 kjournald
   268 root      15   0     0    0     0 SW    0,0  0,0   0:05 kjournald
   269 root      15   0     0    0     0 SW    0,0  0,0   0:00 kjournald
   547 root      15   0     0    0     0 SW    0,0  0,0   0:00 eth0

Cheers, Ruben.


Jan Poslusny wrote:
> Did not your postmaster wait for harddisk ?
>
> Ruben wrote:
>
>> Hi all:
>>
>> When I run a (big) query from pgsql, postmaster used to take almost
>> 100% of CPU. Now, with aparent no reason, Postmaster only takes 4-5%
>> CPU and the same query takes really longer to finish.
>>
>> I have tried renicing -20 postmaster but it still only takes a small
>> percentage of CPU, while 90% is idle.
>>
>> This is a "top" screen while running the query:
>>
>>   2:27pm  up 5 min,  2 users,  load average: 0,80, 0,26, 0,08
>> 74 processes: 72 sleeping, 2 running, 0 zombie, 0 stopped
>> CPU states:  3,1% user,  2,1% system,  0,0% nice, 94,6% idle
>> Mem:  1031012K av,  246040K used,  784972K free,       0K shrd,
>> 11496K buff
>> Swap: 2040244K av,       0K used, 2040244K free
>> 196916K cached
>>
>>   PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM   TIME COMMAND
>>  1165 postgres   0 -20  3476 3476  2912 D <   4,5  0,3   0:02 postmaster
>>   268 root      15   0     0    0     0 SW    0,1  0,0   0:00 kjournald
>>
>> Any idea of how can I get postmaster to eat as much CPU as possible?
>>
>> Thanks a lot! Ruben.
>>
>>
>> ---------------------------(end of broadcast)---------------------------
>> TIP 4: Don't 'kill -9' the postmaster


Re: Postmaster only takes 4-5% CPU

From
"scott.marlowe"
Date:
Under some circumstances, on my (somewhat) older 7.2 box running the 2.4.9
kernel, the kswapd and bdflush daemons will start working overtime when
there are accesses by windows users via samba to look through large
directories.

This makes the box QUITE slow and pokey, and all the tasks that are
running besides kswapd / bdflush are in D state mostly, while the swap
daemon eats 0 to 100% CPU depending on some change in state in samba I've
not bothered tracking down.

I understand a newer kernel might be a good thing for me, so eventually
I'll do that.  For now I just put the Windows Samba people on another box.
They both go through the the same NAS, and it keeps the load off the main
server.

So, look for other processes that might be doing something like scanning a
directory of 40,000 files or some such.

On Thu, 29 May 2003, Ruben wrote:

> Thanks for your answers Jan, Arjen, Shridar and Scott:
>
> Postmaster is back taking lots of CPU when needed. I guess you were
> right about Postgres waiting for some I/O activity. Anyway, I was not
> able to see what process was responsible for this, since top showed
> nothing remarkable.
>
> This is a new top while running a VACUUM of the database:
>
>    8:51pm  up  6:30,  3 users,  load average: 0,45, 0,11, 0,04
> 93 processes: 89 sleeping, 4 running, 0 zombie, 0 stopped
> CPU states:  0,1% user,  1,1% system,  0,0% nice, 98,6% idle
> Mem:  1031012K av, 1019612K used,   11400K free,  0K shrd,   44896K buff
> Swap: 2040244K av,    1716K used, 2038528K free          894008K cached
>
>    PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM   TIME COMMAND
>   1673 postgres  15   0  5120 5120  3196 R     0,9  0,4   0:02 postmaster
>   1683 root      15   0  1044 1044   840 R     0,1  0,1   0:00 top
>      1 root      15   0   476  476   424 S     0,0  0,0   0:04 init
>      2 root      15   0     0    0     0 SW    0,0  0,0   0:00 keventd
>      3 root      15   0     0    0     0 SW    0,0  0,0   0:00 kapmd
>      4 root      34  19     0    0     0 SWN   0,0  0,0   0:00
> ksoftirqd_CPU0
>      5 root      15   0     0    0     0 SW    0,0  0,0   0:00 kswapd
>      6 root      15   0     0    0     0 SW    0,0  0,0   0:00 bdflush
>      7 root      15   0     0    0     0 SW    0,0  0,0   0:00 kupdated
>      8 root      25   0     0    0     0 SW    0,0  0,0   0:00 mdrecoveryd
>     12 root      15   0     0    0     0 SW    0,0  0,0   0:00 kjournald
>     66 root      15   0     0    0     0 SW    0,0  0,0   0:00 khubd
>    266 root      15   0     0    0     0 SW    0,0  0,0   0:00 kjournald
>    267 root      15   0     0    0     0 SW    0,0  0,0   0:00 kjournald
>    268 root      15   0     0    0     0 SW    0,0  0,0   0:05 kjournald
>    269 root      15   0     0    0     0 SW    0,0  0,0   0:00 kjournald
>    547 root      15   0     0    0     0 SW    0,0  0,0   0:00 eth0
>
> Cheers, Ruben.
>
>
> Jan Poslusny wrote:
> > Did not your postmaster wait for harddisk ?
> >
> > Ruben wrote:
> >
> >> Hi all:
> >>
> >> When I run a (big) query from pgsql, postmaster used to take almost
> >> 100% of CPU. Now, with aparent no reason, Postmaster only takes 4-5%
> >> CPU and the same query takes really longer to finish.
> >>
> >> I have tried renicing -20 postmaster but it still only takes a small
> >> percentage of CPU, while 90% is idle.
> >>
> >> This is a "top" screen while running the query:
> >>
> >>   2:27pm  up 5 min,  2 users,  load average: 0,80, 0,26, 0,08
> >> 74 processes: 72 sleeping, 2 running, 0 zombie, 0 stopped
> >> CPU states:  3,1% user,  2,1% system,  0,0% nice, 94,6% idle
> >> Mem:  1031012K av,  246040K used,  784972K free,       0K shrd,
> >> 11496K buff
> >> Swap: 2040244K av,       0K used, 2040244K free
> >> 196916K cached
> >>
> >>   PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM   TIME COMMAND
> >>  1165 postgres   0 -20  3476 3476  2912 D <   4,5  0,3   0:02 postmaster
> >>   268 root      15   0     0    0     0 SW    0,1  0,0   0:00 kjournald
> >>
> >> Any idea of how can I get postmaster to eat as much CPU as possible?
> >>
> >> Thanks a lot! Ruben.
> >>
> >>
> >> ---------------------------(end of broadcast)---------------------------
> >> TIP 4: Don't 'kill -9' the postmaster
>
>
> ---------------------------(end of broadcast)---------------------------
> TIP 2: you can get off all lists at once with the unregister command
>     (send "unregister YourEmailAddressHere" to majordomo@postgresql.org)
>


Re: Postmaster only takes 4-5% CPU

From
Ruben
Date:
Hi:

I'm sorry to get back with this, but I claimed victory too soon.
Postmaster is back (intermitently) taking just a small % of cpu while
system is almost 100% idle, as you can see in "top" below.

Any ideas of how can I fix this? Programs running queries are going too
slooooow.

Thanks!

  11:21am  up 7 days, 21:00,  6 users,  load average: 1,10, 1,04, 0,86
106 processes: 102 sleeping, 4 running, 0 zombie, 0 stopped
CPU states:  0,5% user,  1,7% system,  0,0% nice, 97,6% idle
Mem:  1031012K av, 1019052K used,   11960K free,   0K shrd,  11340K buff
Swap: 2040244K av,  153828K used, 1886416K free           958512K cached

   PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM  TIME COMMAND
23057 postgres  15   0  3316 3136  2292 R     1,1  0,3  0:17 postmaster
23073 postgres  15   0  1096 1096   840 R     0,1  0,1  0:00 top
     1 root      15   0   468  428   416 S     0,0  0,0  0:04 init
     2 root      15   0     0    0     0 SW    0,0  0,0  0:00 keventd
     3 root      15   0     0    0     0 SW    0,0  0,0  0:00 kapmd
     4 root      34  19     0    0     0 SWN   0,0  0,0  0:00 ksoftirqd_C
     5 root      15   0     0    0     0 SW    0,0  0,0  1:18 kswapd
     6 root      15   0     0    0     0 SW    0,0  0,0  0:07 bdflush
     7 root      15   0     0    0     0 SW    0,0  0,0  0:00 kupdated
     8 root      25   0     0    0     0 SW    0,0  0,0  0:00 mdrecoveryd
    12 root      15   0     0    0     0 SW    0,0  0,0  0:00 kjournald
    66 root      15   0     0    0     0 SW    0,0  0,0  0:00 khubd
   266 root      15   0     0    0     0 SW    0,0  0,0  0:00 kjournald
   267 root      15   0     0    0     0 SW    0,0  0,0  0:00 kjournald
   268 root      15   0     0    0     0 SW    0,0  0,0  0:29 kjournald
   269 root      15   0     0    0     0 SW    0,0  0,0  0:00 kjournald
   547 root      15   0     0    0     0 SW    0,0  0,0  0:00 eth0



scott.marlowe wrote:
> Under some circumstances, on my (somewhat) older 7.2 box running the 2.4.9
> kernel, the kswapd and bdflush daemons will start working overtime when
> there are accesses by windows users via samba to look through large
> directories.
>
> This makes the box QUITE slow and pokey, and all the tasks that are
> running besides kswapd / bdflush are in D state mostly, while the swap
> daemon eats 0 to 100% CPU depending on some change in state in samba I've
> not bothered tracking down.
>
> I understand a newer kernel might be a good thing for me, so eventually
> I'll do that.  For now I just put the Windows Samba people on another box.
> They both go through the the same NAS, and it keeps the load off the main
> server.
>
> So, look for other processes that might be doing something like scanning a
> directory of 40,000 files or some such.
>
> On Thu, 29 May 2003, Ruben wrote:
>
>
>>Thanks for your answers Jan, Arjen, Shridar and Scott:
>>
>>Postmaster is back taking lots of CPU when needed. I guess you were
>>right about Postgres waiting for some I/O activity. Anyway, I was not
>>able to see what process was responsible for this, since top showed
>>nothing remarkable.
>>
>>This is a new top while running a VACUUM of the database:
>>
>>   8:51pm  up  6:30,  3 users,  load average: 0,45, 0,11, 0,04
>>93 processes: 89 sleeping, 4 running, 0 zombie, 0 stopped
>>CPU states:  0,1% user,  1,1% system,  0,0% nice, 98,6% idle
>>Mem:  1031012K av, 1019612K used,   11400K free,  0K shrd,   44896K buff
>>Swap: 2040244K av,    1716K used, 2038528K free          894008K cached
>>
>>   PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM   TIME COMMAND
>>  1673 postgres  15   0  5120 5120  3196 R     0,9  0,4   0:02 postmaster
>>  1683 root      15   0  1044 1044   840 R     0,1  0,1   0:00 top
>>     1 root      15   0   476  476   424 S     0,0  0,0   0:04 init
>>     2 root      15   0     0    0     0 SW    0,0  0,0   0:00 keventd
>>     3 root      15   0     0    0     0 SW    0,0  0,0   0:00 kapmd
>>     4 root      34  19     0    0     0 SWN   0,0  0,0   0:00
>>ksoftirqd_CPU0
>>     5 root      15   0     0    0     0 SW    0,0  0,0   0:00 kswapd
>>     6 root      15   0     0    0     0 SW    0,0  0,0   0:00 bdflush
>>     7 root      15   0     0    0     0 SW    0,0  0,0   0:00 kupdated
>>     8 root      25   0     0    0     0 SW    0,0  0,0   0:00 mdrecoveryd
>>    12 root      15   0     0    0     0 SW    0,0  0,0   0:00 kjournald
>>    66 root      15   0     0    0     0 SW    0,0  0,0   0:00 khubd
>>   266 root      15   0     0    0     0 SW    0,0  0,0   0:00 kjournald
>>   267 root      15   0     0    0     0 SW    0,0  0,0   0:00 kjournald
>>   268 root      15   0     0    0     0 SW    0,0  0,0   0:05 kjournald
>>   269 root      15   0     0    0     0 SW    0,0  0,0   0:00 kjournald
>>   547 root      15   0     0    0     0 SW    0,0  0,0   0:00 eth0
>>
>>Cheers, Ruben.
>>
>>
>>Jan Poslusny wrote:
>>
>>>Did not your postmaster wait for harddisk ?
>>>
>>>Ruben wrote:
>>>
>>>
>>>>Hi all:
>>>>
>>>>When I run a (big) query from pgsql, postmaster used to take almost
>>>>100% of CPU. Now, with aparent no reason, Postmaster only takes 4-5%
>>>>CPU and the same query takes really longer to finish.
>>>>
>>>>I have tried renicing -20 postmaster but it still only takes a small
>>>>percentage of CPU, while 90% is idle.
>>>>
>>>>This is a "top" screen while running the query:
>>>>
>>>>  2:27pm  up 5 min,  2 users,  load average: 0,80, 0,26, 0,08
>>>>74 processes: 72 sleeping, 2 running, 0 zombie, 0 stopped
>>>>CPU states:  3,1% user,  2,1% system,  0,0% nice, 94,6% idle
>>>>Mem:  1031012K av,  246040K used,  784972K free,       0K shrd,
>>>>11496K buff
>>>>Swap: 2040244K av,       0K used, 2040244K free
>>>>196916K cached
>>>>
>>>>  PID USER     PRI  NI  SIZE  RSS SHARE STAT %CPU %MEM   TIME COMMAND
>>>> 1165 postgres   0 -20  3476 3476  2912 D <   4,5  0,3   0:02 postmaster
>>>>  268 root      15   0     0    0     0 SW    0,1  0,0   0:00 kjournald
>>>>
>>>>Any idea of how can I get postmaster to eat as much CPU as possible?
>>>>
>>>>Thanks a lot! Ruben.
>>>>
>>>>
>>>>---------------------------(end of broadcast)---------------------------
>>>>TIP 4: Don't 'kill -9' the postmaster
>>>
>>
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Re: Postmaster only takes 4-5% CPU

From
Jamie Lawrence
Date:
On Fri, 06 Jun 2003, Ruben wrote:

> Hi:
>
> I'm sorry to get back with this, but I claimed victory too soon.
> Postmaster is back (intermitently) taking just a small % of cpu while
> system is almost 100% idle, as you can see in "top" below.
>
> Any ideas of how can I fix this? Programs running queries are going too
> slooooow.

>  11:21am  up 7 days, 21:00,  6 users,  load average: 1,10, 1,04, 0,86
> 106 processes: 102 sleeping, 4 running, 0 zombie, 0 stopped
> CPU states:  0,5% user,  1,7% system,  0,0% nice, 97,6% idle
> Mem:  1031012K av, 1019052K used,   11960K free,   0K shrd,  11340K buff
> Swap: 2040244K av,  153828K used, 1886416K free           958512K cached

What does the output of 'vmstat 5 15' look like while you're running the
query? (that command will run for 75 seconds.)

I'm willing to bet your problem is I/O contention.

-j


--
Jamie Lawrence                                        jal@jal.org
"Many and loud have been the voices crying that Aids was God's
way of punishing an unnatural practice. One day, perhaps, an
inoculation against HIV may be discovered. A bottle of champagne,
then, for whoever cites me evidence of one of those voices
crying that the breakthrough is God's way of telling us to
bugger each other."
   - Matthew Parris


Re: Postmaster only takes 4-5% CPU

From
Ruben
Date:
Thanks Jamie:

I'll send the output of vmstat next time this happens.

Ruben.

Jamie Lawrence wrote:
> On Fri, 06 Jun 2003, Ruben wrote:
>
>
>>Hi:
>>
>>I'm sorry to get back with this, but I claimed victory too soon.
>>Postmaster is back (intermitently) taking just a small % of cpu while
>>system is almost 100% idle, as you can see in "top" below.
>>
>>Any ideas of how can I fix this? Programs running queries are going too
>>slooooow.
>
>
>
>> 11:21am  up 7 days, 21:00,  6 users,  load average: 1,10, 1,04, 0,86
>>106 processes: 102 sleeping, 4 running, 0 zombie, 0 stopped
>>CPU states:  0,5% user,  1,7% system,  0,0% nice, 97,6% idle
>>Mem:  1031012K av, 1019052K used,   11960K free,   0K shrd,  11340K buff
>>Swap: 2040244K av,  153828K used, 1886416K free           958512K cached
>
>
> What does the output of 'vmstat 5 15' look like while you're running the
> query? (that command will run for 75 seconds.)
>
> I'm willing to bet your problem is I/O contention.
>
> -j