Re: Get rid of WALBufMappingLock

On Tue, Feb 25, 2025 at 05:19:29PM +0200, Alexander Korotkov wrote:
> It seems that I managed to reproduce the issue on my Raspberry PI 4.
> After running our test suite in a loop for 2 days I found one timeout.

Hmm.  It's surprising to not see a higher occurence.  My buildfarm
host has caught that on its first run after the patch, for two
different animals which are both on the same machine.

> One way or another, we need protection against this situation any way.
> The updated patch is attached.  Now, after acquiring ReservedPtr it
> waits till OldPageRqstPtr gets initialized.  Additionally I've to
> implement more accurate calculation of OldPageRqstPtr.  I run tests
> with new patch on my Raspberry in a loop.  Let's see how it goes.

Perhaps you'd prefer that I do more tests with your patch?  This is
time-consuming for you.  This is not a review of the internals of the
patch, and I cannot give you access to the host, but if my stuff is
the only place where we have a good reproducibility of the issue, I'm
OK to grab some time and run a couple of checks to avoid again a
freeze of the buildfarm.
--
Michael