Re: [HACKERS] Re: [PATCHES] patches for 6.2.1p6

On Mon, 16 Mar 1998, David Gould wrote:

> The generic way to do this is
>
> select( NULL_FDSET, NULL_FDSET, NULL_FDSET, &delaytime, NULL);
>
> Delay time may be 0, but a random value between 0 and say 30 msec seems
> to be optimal. Hard busy wait spinlocks cause huge performance problems with
> heavily loaded systems and lots of postgres backends. Basically one backend
> ends up with the lock and gets scheduled out holding it, every else queues
> up busywaiting behind this one. But the backend holding the lock cannot
> release it until all the other backeds waiting on the lock exhaust a full
> timeslice busywaiting. Get 20 of these guys going (like on a busy website) and
> the system pretty much stops doing any work at all.
>
> I say we should get this in as soon as we can.

Can you submit an appropriate patch that can be included in the mega-patch
to be created on Sunday?

Thanks...

Marc G. Fournier
Systems Administrator @ hub.org
primary: scrappy(at)hub(dot)org secondary: scrappy(at){freebsd|postgresql}.org