Re: Patch to improve performance of replay of AccessExclusiveLock

On 8 March 2017 at 10:02, David Rowley <david(dot)rowley(at)2ndquadrant(dot)com> wrote:
> On 8 March 2017 at 01:13, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
>> Don't understand this. I'm talking about setting a flag on
>> commit/abort WAL records, like the attached.
>
> There's nothing setting a flag in the attached. I only see the
> checking of the flag.

Yeh, it wasn't a full patch, just a way marker to the summit for you.

>> We just need to track info so we can set the flag at EOXact and we're done.
>
> Do you have an idea where to store that information? I'd assume we'd
> want to store something during LogAccessExclusiveLocks() and check
> that in XactLogCommitRecord() and XactLogAbortRecord(). I don't see
> anything existing which might help with that today. Do you think I
> should introduce some new global variable for that? Or do you propose
> calling GetRunningTransactionLocks() again while generating the
> Commit/Abort record?

Seemed easier to write it than explain further. Please see what you think.

--
Simon Riggs http://www.2ndQuadrant.com/
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