Re: Patch: Write Amplification Reduction Method (WARM)

Pavan Deolasee wrote:

> Do you think we should apply the patch to remove ItemPointerCopy()? I will
> rework the HeapTupleHeaderGetNextTid() after that. Not that it depends on
> removing ItemPointerCopy(), but decided to postpone it until we make a call
> on that patch.

My inclination is not to. We don't really know where we are going with
storage layer reworks in the near future, and we might end up changing
this in other ways. We might find ourselves needing this kind of
abstraction again. I don't think this means we need to follow it
completely in new code, since it's already broken in other places, but
let's not destroy it completely just yet.

> BTW I've run now long stress tests with the patch applied and see no new
> issues, even when indexes are dropped and recreated concurrently (includes
> my patch to fix CIC bug in the master though). In another 24 hour test,
> WARM could do 274M transactions where as master did 164M transactions. I
> did not drop and recreate indexes during this run.

Eh, that's a 67% performance improvement. Nice.

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Álvaro Herrera https://www.2ndQuadrant.com/
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