Re: Oracle/Solaris Kernel Tunables Question

Wavey <dave_at_nospam35ad.com> wrote in message news:<n87o5b.1h2.ln_at_192.168.1.245>...
> The rule of thumb i use is
>
> set shmmax to size of phys memory or the maximum expected sga size
> set shmseg to a value that will allow multiple segments.
> This is less important if shmmax is sized right
> set shmmni to a value representing the maximum # of instances you expect to run on the box (+
> any shared memory requirements of non oracle apps)
>
> Normally you configure these to allow oracle to get the shared mem for the sga in 1 contigous segment.

The rule of thumb of setting shmmax to "phys memory or the maximum expected sga size" might be a valid point many years ago. From at least 8.1.6 down, Oracle database installation guide proposes setting it to the theoretical limit (e.g. 4 billion on 32-bit OS). Richard McDougall in "Solaris Internals" also says setting it to the limit is completely harmless.

Yong Huang Received on Tue Mar 25 2003 - 13:04:45 CST