Re: Re: Red Hat to support PostgreSQL

> I had almost given up on using Postgres for this system because under
> Solaris, it just couldn't cut it (MySQL could do the work with one CPU
> while Postgres took up even more CPU and required *both* CPUs to be
> enabled), but when we moved the system to a Linux box, things worked
> much better.

Ah, back to a PostgreSQL topic. :-)

My guess on this one is that Solaris is slower for PostgreSQL because
process switching is _much_ heavier on Solaris than other OS's. This is
because of the way they implemented processes in SVr4. They got quite
heavy, almost requiring kernel threads so you weren't switching
processes all the time.

In a sense threads were a solution to a process bloating problem.
Linux/BSD have much lighter processes and hence work better for
PostgreSQL. Again, this is only a guess.

MySQL does more stuff with threads while PostgreSQL switches process
because each backend is a process.

--
Bruce Momjian | http://candle.pha.pa.us
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