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Free memory usage Sol10, 8.2.9
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* Free memory usage Sol10, 8.2.9
@ 2009-11-03 19:16 Subbiah Stalin-XCGF84 <SSubbiah@Motorola.com>
  2009-11-03 20:42 ` Re: Free memory usage Sol10, 8.2.9 Jeremy Harris <jgh@wizmail.org>
  0 siblings, 1 reply; 3+ messages in thread

From: Subbiah Stalin-XCGF84 @ 2009-11-03 19:16 UTC (permalink / raw)
  To: pgsql-performance

All,
 
I'm trying to understand the free memory usage and why it falls below
17G sometimes and what could be causing it. Any pointers would be
appreciated.
 
root@prod1 # prtconf
System Configuration:  Sun Microsystems  sun4u
Memory size: 32768 Megabytes
 
[postgres@prod1 ~]$ vmstat 5 10
 kthr      memory            page            disk          faults
cpu
 r b w   swap  free  re  mf pi po fr de sr 1m 1m 1m m1   in   sy   cs us
sy id
 0 0 0 51713480 21130304 58 185 325 104 104 0 0 23 3 7 1 488 604  573  1
2 97
 0 0 0 51048768 18523456 6 10 0 192 192 0 0 4  0  3  0  527  753  807  2
1 97
 0 0 0 51713480 21130304 58 185 325 104 104 0 0 1 23 3 7 488 604  573  1
2 97
 0 0 0 51067112 18538472 0 1 0 171 171 0 0  4  8  0  4  522  573  740  2
1 97
 0 0 0 51072744 18542992 0 0 0 187 187 0 0  0 22  0  7  532  657  780  2
1 97
 0 0 0 51069944 18540736 146 1729 3 174 174 0 0 0 9 0 3 526 3227  944  4
5 91
 0 0 0 51065728 18537360 32 33 0 192 192 0 0 0 20 0  3  522 1147  927  3
2 95
 0 0 0 51065728 18537336 0 0 0 190 190 0 0  0 26  0  3  517  628  789  2
1 97
 0 0 0 51065728 18537336 0 0 0 168 168 0 0  0 25  0 11  517  668  810  2
2 96
 0 0 0 51062960 18535152 0 165 2 190 190 0 0 14 29 0 4  552  732  808  2
1 97
 
prstat -am
 
 NPROC USERNAME  SWAP   RSS MEMORY      TIME  CPU
    21 postgres 8312M 8300M    25% 112:24:15 2.1%
    53 root      347M  236M   0.7% 130:52:02 0.1%
     7 daemon    708M  714M   2.2%  21:53:05 0.0%
     4 mot      5552K   15M   0.0%   0:00:00 0.0%
     1 smmsp    1384K 5480K   0.0%   0:00:59 0.0%


[postgres@prod1]$ ps -eaf | grep postgres | wc -l
24
 
max_connections = 600
shared_buffers = 8000MB 
temp_buffers = 8MB
work_mem = 2MB                          
maintenance_work_mem = 256MB            
max_fsm_pages = 2048000
max_fsm_relations = 2000
effective_cache_size = 4000MB
 
Thanks,
Stalin

 
 

^ permalink  raw  reply  [nested|flat] 3+ messages in thread

* Re: Free memory usage Sol10, 8.2.9
  2009-11-03 19:16 Free memory usage Sol10, 8.2.9 Subbiah Stalin-XCGF84 <SSubbiah@Motorola.com>
@ 2009-11-03 20:42 ` Jeremy Harris <jgh@wizmail.org>
  2009-11-04 10:35   ` Re: Free memory usage Sol10, 8.2.9 Ivan Voras <ivoras@freebsd.org>
  0 siblings, 1 reply; 3+ messages in thread

From: Jeremy Harris @ 2009-11-03 20:42 UTC (permalink / raw)
  To: pgsql-performance

On 11/03/2009 07:16 PM, Subbiah Stalin-XCGF84 wrote:
> All,
>
> I'm trying to understand the free memory usage and why it falls below
> 17G sometimes and what could be causing it. Any pointers would be
> appreciated.
>
> root@prod1 # prtconf
> System Configuration:  Sun Microsystems  sun4u
> Memory size: 32768 Megabytes
>
> [postgres@prod1 ~]$ vmstat 5 10
>   kthr      memory            page            disk          faults
> cpu
>   r b w   swap  free  re  mf pi po fr de sr 1m 1m 1m m1   in   sy   cs us
> sy id
>   0 0 0 51713480 21130304 58 185 325 104 104 0 0 23 3 7 1 488 604  573  1
> 2 97
>   0 0 0 51048768 18523456 6 10 0 192 192 0 0 4  0  3  0  527  753  807  2
> 1 97

Memory used by the OS for caching files is no longer free.
Free memory is wasted memory.
-J



^ permalink  raw  reply  [nested|flat] 3+ messages in thread

* Re: Free memory usage Sol10, 8.2.9
  2009-11-03 19:16 Free memory usage Sol10, 8.2.9 Subbiah Stalin-XCGF84 <SSubbiah@Motorola.com>
  2009-11-03 20:42 ` Re: Free memory usage Sol10, 8.2.9 Jeremy Harris <jgh@wizmail.org>
@ 2009-11-04 10:35   ` Ivan Voras <ivoras@freebsd.org>
  0 siblings, 0 replies; 3+ messages in thread

From: Ivan Voras @ 2009-11-04 10:35 UTC (permalink / raw)
  To: pgsql-performance

Jeremy Harris wrote:
> On 11/03/2009 07:16 PM, Subbiah Stalin-XCGF84 wrote:
>> All,
>>
>> I'm trying to understand the free memory usage and why it falls below
>> 17G sometimes and what could be causing it. Any pointers would be
>> appreciated.
>>
>> root@prod1 # prtconf
>> System Configuration:  Sun Microsystems  sun4u
>> Memory size: 32768 Megabytes
>>
>> [postgres@prod1 ~]$ vmstat 5 10
>>   kthr      memory            page            disk          faults
>> cpu
>>   r b w   swap  free  re  mf pi po fr de sr 1m 1m 1m m1   in   sy   cs us
>> sy id
>>   0 0 0 51713480 21130304 58 185 325 104 104 0 0 23 3 7 1 488 604  573  1
>> 2 97
>>   0 0 0 51048768 18523456 6 10 0 192 192 0 0 4  0  3  0  527  753  807  2
>> 1 97
> 
> Memory used by the OS for caching files is no longer free.
> Free memory is wasted memory.

To finish the thought: memory used by OS for caching files will be 
automatically given to applications that need more memory so it is "kind 
of" free memory.

In your case, you really do have 17-18G unused memory which is 
practically wasted.




^ permalink  raw  reply  [nested|flat] 3+ messages in thread


end of thread, other threads:[~2009-11-04 10:35 UTC | newest]

Thread overview: 3+ messages (download: mbox mbox.gz follow: Atom feed)
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2009-11-03 19:16 Free memory usage Sol10, 8.2.9 Subbiah Stalin-XCGF84 <SSubbiah@Motorola.com>
2009-11-03 20:42 ` Jeremy Harris <jgh@wizmail.org>
2009-11-04 10:35   ` Ivan Voras <ivoras@freebsd.org>

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