> > > > We could use POSIX spinlocks/semaphores now but we
> > > > don't because of performance, right?
> > >
> > > No. As long as no one proved with test that mutexes are bad for
> > > performance...
> > > Funny, such test would require ~ 1 day of work.
> > Good question. I know the number of function calls to spinlock stuff
> > is huge. Seems real semaphores may be a big win on multi-cpu boxes.
> Ok, being tired of endless discussions I'll try to use mutexes instead
> of spinlocks and run pgbench on my Solaris WS 10 and E4500 (4 CPU) boxes.
I have updated the TODO list with:
* Improve spinlock code
o use SysV semaphores or queue of backends waiting on the lock
o wakeup sleeper or sleep for less than one clock tick
o spin for lock on multi-cpu machines, yield on single cpu machines
o read/write locks
Bruce Momjian | http://candle.pha.pa.us
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