Re: [HACKERS] Re: [PATCHES] S_LOCK reduced contention through backoff patch

Ocie: 
> David Gould wrote:
> 
> [snip]
> > Here is the Spinlock back off patch I promised. This does semi-random
> > backoff using select() to lessen throughput degradation due to spinlock
> > contention with large numbers of runnable backends.
> 
> Does this actually use some sort of random number generator?  I'm

No. Have a look at the patch.

> thinking that this may not be entirely necessary.  With Ethernet, this
> is needed to avoid another colission, but with locks, one process is
> guaranteed to get a lock.

In the case where this comes into play, one process already has the lock.
We have already collided. We are trying to limit the number of additional
collisions.

-dg


David Gould            dg@illustra.com           510.628.3783 or 510.305.9468 
Informix Software  (No, really)         300 Lakeside Drive  Oakland, CA 94612
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