Re: spinlocks on HP-UX

On Tue, Sep 6, 2011 at 4:33 AM, Tatsuo Ishii <ishii(at)postgresql(dot)org> wrote:
> I am interested in this thread because I may be able to borrow a big
> IBM machine and might be able to do some tests on it if it somewhat
> contributes enhancing PostgreSQL. Is there anything I can do for this?

That would be great. What I've been using as a test case is pgbench
-S -c $NUM_CPU_CORES -j $NUM_CPU_CORES with scale factor 100 and
shared_buffers=8GB.

I think what you'd want to compare is the performance of unpatched
master, vs. the performance with this line added to s_lock.h for your
architecture:

#define TAS_SPIN(lock) (*(lock) ? 1 : TAS(lock))

We've now added that line for ia64 (the line is present in two
different places in the file, one for GCC and the other for HP's
compiler). So the question is whether we need it for any other
architectures.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company