Marko Tiikkaja wrote:
> On the test server I'm running on, it doesn't look quite as bad as the
> profiles we had in production, but s_lock is still the worst offender in the
> profiles, called from:
>
> - 80.33% LWLockAcquire
> + 48.34% asyncQueueReadAllNotifications
> + 23.09% SIGetDataEntries
> + 16.92% SimpleLruReadPage_ReadOnly
> + 10.21% TransactionIdIsInProgress
> + 1.27% asyncQueueAdvanceTail
>
> which roughly looks like what I recall from our actual production profiles.
So the problem is in the bad scalability of LWLock, not in async.c itself?
In master, the spinlock there has been replaced with atomics; does that branch
work better?
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Álvaro Herrera http://www.2ndQuadrant.com/
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