Re: 7.1 vs. 7.2 on AIX 5L - Mailing list pgsql-hackers

> On my machine the various implemtations have the following runtimes:
> (with a modified s_lock test that does not sleep, and 
> SPINS_PER_DELAY 100000)
> 
> with LinuxPPC asm:     1m5.16s    (Which may not work relyably on SMP)
> with cs:            1m12.25s
> with fetch_and_or:    1m26.71s

Aah, there we have it. Same test on a slower 4Way SMP:

with LinuxPPC asm:     2m9.340s
with cs:            10m11.15s
with fetch_and_or:    3m55.19s

These numbers look more alarming.
Unfortunately the man page for fetch_and_or does not mention anything 
about using it as a locking primitive. It is documented atomic though,
so I guess that is enough.

Andreas