NetComrade wrote:
> On Mon, 15 Jan 2007 10:48:05 -0800, DA Morgan <damorgan_at_psoug.org>
> wrote:
>
>>> sysctl:
>>> fs.file-max = 65536
>>> kernel.shmall = 1572864
>>> kernel.sem = 1000 32000 100 128
>>> kernel.shmmax = 6442450944
>>> net.ipv4.ip_local_port_range = 1024 65000
>>> vm.nr_hugepages=3100
>>>
>>> .......
>>> We run Oracle 9iR2,10gR1/2 on RH4/RH3 and Solaris 10 (Sparc)
>>> remove NSPAM to email
>> Run the following as root
>>
>> /sbin/sysctl -p
>>
>> and compare with Oracle's recommendations which will be something
>> close to this:
>>
>> fs.file-max = 65536
>> kernel.shmall = 2097152
>> kernel.shmmax = 2147483648
>> kernel.shmmni = 4096
>> kernel.sem = 250 32000 100 128
>> net.core.rmem_default = 1048576
>> net.core.rmem_max = 1048576
>> net.core.wmem_default = 262144
>> net.core.wmem_max = 262144
>> net.ipv4.ip_forward = 0
>> net.ipv4.conf.default.rp_filter = 1
>> net.ipv4.ip_local_port_range = 1024 65000
>
> Daniel, all the rmem/wmem parameter were actually recommended for 10g
> dbs.. I fail to see how any of these will help with my IO problem
> though :)
>
> http://www.puschitz.com/TuningLinuxForOracle.shtml#SettingSharedMemory
>
> (how the first 4 are set on linux:
> kernel.sem = SEMMSL SEMMNS SEMOPM SEMMNI
> Here's the recommendations for 9i on linux x64 (metalink note)
> SEMMSL 250 (processes + 10, ours is 1000)
> SEMMNS 32000 (processes across all instances. total semaphores)
> SEMMNI 128 (max # of shared memory segments, we have this set ot
> recommended)
> SEMOPM 100 (max # of of semaphore ops, we should've set tihs to 250
> per link above)
> SEMVMX 32767 (semvmx specifies the maximum possible semaphore value,
> kernel default)
> SHMMAX 2147483648 (max sga, our sga is 3G, or shmax is 6g)
> One-half the size of your system's physical memory. Check your system
> for additional restrictions.
> SHMMNI 4096 (This parameter sets the system wide maximum number of
> shared memory segments)
> SHMALL = SHMMAX/pagesize (our matches
> FILE-MAX 65536
> IP_LOCAL_PORT_RANGE 1024 65000
>
> The only thing we have probably set wrong is this: "Free system memory
> will automatically be decreased by the size of the Huge Pages pool
> allocation regardless whether the pool is being used by an application
> like Oracle DB or not: "
>
> However, I tried decreasing those during RMAN level 0, and it didnt
> seem to help
It was just a vanilla recommendation when I saw parameters that didn't
look like the defaults. Basically elimination of the low hanging fruit.
--
Daniel A. Morgan
University of Washington
damorgan_at_x.washington.edu
(replace x with u to respond)
Puget Sound Oracle Users Group
www.psoug.org
Received on Mon Jan 15 2007 - 23:11:51 CST
