Re: buffer assertion tripping under repeat pgbench load

On 12/23/12 3:17 PM, Simon Riggs wrote:
> We already have PrintBufferLeakWarning() for this, which might be a bit neater.

Maybe. I tried using this, and I just got a seg fault within that code.
I can't figure out if I called it incorrectly or if the buffer
involved is so damaged that PrintBufferLeakWarning chokes on it. I'll
look at that myself later.

I did get some output from the variation Andres suggested. There was
exactly one screwed up buffer:

2012-12-24 06:08:46 EST [26015]: WARNING: refcount of base/16384/49169
is 1073741824 should be 0, globally: 0

That is pgbench_accounts_pkey. 1073741824 =
0100 0000 0000 0000 0000 0000 0000 0000 = 2^30

Pretty odd value to find in a PrivateRefCount. What makes me nervous
about all of the PrivateRefCount coding is how it switches between
references like PrivateRefCount[(bufnum) - 1] and PrivateRefCount[b].
Might this be an off by one error in one of those, where the wrong form
was used?

--
Greg Smith 2ndQuadrant US greg(at)2ndQuadrant(dot)com Baltimore, MD
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