PostgreSQL7.1 on AIX5L is running with too poor ferformance

Started by Leslieover 24 years ago3 messages
#1Leslie
leslie@boreas.dti.ne.jp

Hi

PostgreSQL7.1 is now running on AIX5L( S85, 6GB memory, 6CPU), which was
running on Linux before(Pentium3, 2CPU, as far as I
remember.......sorry......).
The performance( on AIX5L ) is just half as good as the one( on Linux ).
I compiled PostgreSQL on AIX5L ofcourse.
I haven't configured it when migrating to AIX5L though.
Are there any problems in not tuning when migrating it to AIX5L?
What should I check first?
I can't make a head or tail of it:(
Help!!

Best regards,
Shuichi

#2Tom Lane
tgl@sss.pgh.pa.us
In reply to: Leslie (#1)
Re: PostgreSQL7.1 on AIX5L is running with too poor ferformance

"Leslie" <leslie@boreas.dti.ne.jp> writes:

PostgreSQL7.1 is now running on AIX5L( S85, 6GB memory, 6CPU), which was
running on Linux before(Pentium3, 2CPU, as far as I
remember.......sorry......).
The performance( on AIX5L ) is just half as good as the one( on Linux ).

Hmm ... is the AIX compilation selecting an appropriate TAS
implementation for spinlocks? If it's falling back to semaphore-based
spinlocks, I can easily believe that you might take a 2X performance
hit. Possibly s_lock.h needs some additional #if tests for AIX5.

regards, tom lane

#3Tatsuo Ishii
t-ishii@sra.co.jp
In reply to: Tom Lane (#2)
Re: PostgreSQL7.1 on AIX5L is running with too poor ferformance

"Leslie" <leslie@boreas.dti.ne.jp> writes:

PostgreSQL7.1 is now running on AIX5L( S85, 6GB memory, 6CPU), which was
running on Linux before(Pentium3, 2CPU, as far as I
remember.......sorry......).
The performance( on AIX5L ) is just half as good as the one( on Linux ).

Hmm ... is the AIX compilation selecting an appropriate TAS
implementation for spinlocks?

I think yes. I have compiled 7.1 on an AIX5L box and found that TAS()
was replaced by:

cs((int *) (lock), 0, 1)

If it's falling back to semaphore-based
spinlocks, I can easily believe that you might take a 2X performance
hit. Possibly s_lock.h needs some additional #if tests for AIX5.

--
Tatsuo Ishii