Re: s_lock() seems too aggressive for machines with many sockets

Jan Wieck <jan@wi3ck.info> writes:
> The attached patch demonstrates that less aggressive spinning and (much) 
> more often delaying improves the performance "on this type of machine". 

Hm.  One thing worth asking is why the code didn't converge to a good
value of spins_per_delay without help.  The value should drop every time
we had to delay, so under heavy contention it ought to end up small
anyhow, no?  Maybe we just need to alter the feedback loop a bit.

(The comment about uniprocessors vs multiprocessors seems pretty wacko in
this context, but at least the sign of the feedback term seems correct.)
        regards, tom lane