Re: [PATCHES] update i386 spinlock for hyperthreading

Tom Lane wrote:
> Jan Wieck <JanWieck(at)Yahoo(dot)com> writes:
> >> That's irrelevant to the problem, though. Unless the ARC code uses data
> >> structures that are more amenable to localized locking than the old
> >> global buffer freelist. (Jan?)
>
> > the strategy itself does no locking at all. Like the old LRU code it
> > simply assumes that the buffer manager holds the lock during calls.
>
> Okay, I suspected as much but wasn't sure.
>
> Manfred's numbers definitely say that we need to find a way to break
> down the BufMgrLock into multiple finer-grain locks. We already have
> all those per-buffer LWLocks, but I don't see how to apply those to
> the problem of managing the global lookup and replacement datastructures.
>
> Anyone see an attack path here?

Should we have one lock per hash bucket rather than one for the entire
hash?

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