Re: Question about LWLockAcquire's use of semaphores instead of spinlocks

Tom Lane writes:
>
>
> "Robert E. Bruccoleri" <bruc(at)stone(dot)congenomics(dot)com> writes:
> > On SGI multiprocessor machines, I suspect that a spinlock
> > implementation of LWLockAcquire would give better performance than
> > using IPC semaphores. Is there any specific reason that a spinlock
> > could not be used in this context?
>
> Are you confusing LWLockAcquire with TAS spinlocks?

No.

> If you're saying that we don't have an implementation of TAS for
> SGI hardware, then feel free to contribute one. If you are wanting to
> replace LWLocks with spinlocks, then you are sadly mistaken, IMHO.

This touches on my question. Why am I mistaken? I don't understand.

BTW, about 5 years ago, I rewrote the TAS spinlocks for the
SGI platform to make it work correctly. The current implementation
is fine.

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| Robert E. Bruccoleri, Ph.D. | email: bruc(at)acm(dot)org |
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