Hi Nicolas,

Thanks. I will collect the ipcs data which you suggested.

Another question,for the "prstat", I found there are three sybase processes
as below:

# prstat -a
   PID USERNAME  SIZE   RSS STATE  PRI NICE      TIME  CPU PROCESS/NLWP
 10032 sybase   7779M 7762M cpu10   20    0  22:20:52 9.7% dataserver/12
 10077 sybase   7779M 7762M sleep   50    0  22:38:45 4.4% dataserver/12
 10078 sybase   7779M 7762M sleep   52    0  22:29:03 3.9% dataserver/12
...

Does mean there are total 3 sysbase instance running(or actually only one
instance) ? and *each *instance used 7779M vm and 7762M physcial RAM ?

Thanks.
Best Regards,
Simon


On Thu, Nov 26, 2009 at 4:24 AM, Nicolas Dorfsman <[email protected]> wrote:

>
> Le 22 nov. 2009 à 15:35, Simon a écrit :
>
> Hi Nicolas,
>
> Thank you.
>
> I think adding extra swap device would not be helpful in our case,because
> the customer appliction created too many stack/heaps,these anonymous memory
> has to use swap device as back store,if the physical RAM really
> shortage,more swap device only cause page out cost and performance will be
> degraded accordingly,right ?
>
>
> Right. Except in one case....DISM use of shared memory.
> Take a look to this command :
>
> # ipcs -ZAm | awk 'NR>1&&$16>0{s+=$10} END{print "total=", s/1024}'
>
>
> If there's something different than 0, your Sybase is using DISM segments.
> With DISM, there's a double 'reservation'....one at creation time, and
> another at attach time. 'Reservation' doesn't mean 'utilisation', the only
> way to have sufficient 'rerservation' space is to add swap. Nothing will be
> swapped out because it's only a reservation.   It's just a security to be
> able to swap out theses segments in case of DR.
>
>
> Nicolas
>
>
>
>
>
> Thanks.
> Best Regards,
> Simon
>
>
> On Sat, Nov 21, 2009 at 8:01 PM, Nicolas Dorfsman <[email protected]> wrote:
>
>>
>>        Hi Simon,
>>
>> Le 21 nov. 09 à 07:27, Simon a écrit :
>>
>>
>>> # ipcs -a
>>> IPC status from <running system> as of Thu Nov 12 12:05:28 HKT 2009
>>> T         ID      KEY        MODE        OWNER    GROUP  CREATOR   CGROUP
>>> CBYTES  QNUM QBYTES LSPID LRPID   STIME    RTIME    CTIME
>>> Message Queues:
>>> T         ID      KEY        MODE        OWNER    GROUP  CREATOR   CGROUP
>>> NATTCH      SEGSZ  CPID  LPID   ATIME    DTIME    CTIME
>>> Shared Memory:
>>> m          3   0xe9032d40 --rw-------   sybase    staff   sybase    staff
>>>      3  738803712  1314  2125 20:47:22 no-entry 20:47:14
>>> m          2   0x51       --rw-rw-r--     root     root     root     root
>>>      1    2000196  2122  8553 15:15:18 15:15:23 13:14:38
>>> m          1   0x50       --rw-rw-r--     root     root     root     root
>>>      1     600196  2121  2121 13:14:38 no-entry 13:14:38
>>> m          0   0xe9032d32 --rw-------   sybase    staff   sybase    staff
>>>      3 7851147264  1314  2125 13:14:40 13:14:40 13:13:42
>>> T         ID      KEY        MODE        OWNER    GROUP  CREATOR   CGROUP
>>> NSEMS   OTIME    CTIME
>>> Semaphores:
>>> s          1   0x51       --ra-ra-ra-     root     root     root     root
>>>     6 12:05:28 13:14:38
>>> s          0   0x50       --ra-ra-ra-     root     root     root     root
>>>     6 12:05:28 13:14:38
>>>
>>
>>        I'm not sure about Sybase and ISM/DISM, but you may take a look to
>> ISM/DISM segments by :
>>
>> # ipcs -ZAm | awk 'NR>1&&$16>0{s+=$10} END{print "total=", s/1024}'
>>
>> DISM segments may suffer of double allocation algorithm.  The Workaround
>> is to add as many disk-swap-area as your SGBD SHM reservation.
>> I've wrote an article on that (
>> http://www.solaris-fr.org/home/docs/base/memoire), but in french for now,
>> sorry.
>>
>> Nicolas
>
>
>
>
_______________________________________________
sysadmin-discuss mailing list
[email protected]
http://mail.opensolaris.org/mailman/listinfo/sysadmin-discuss

Reply via email to