>> pgsql 7.3 cannot take advantage of lots of shared memory, and has some
>> issues scaling to lots of CPUs / processes.
>
> I use RHEL 4. I can not understand how the scalability related with
> shared memory?
It isn't RHEL4 and shared memory. It is PostgreSQL and shared memory.
Things have changed with PostgreSQL since 7.3 (7.3 is really god awful
old) that allow it to more effectively access shared memory and thus
provide better performance.
Joshua D. Drake
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