Re: [HACKERS] new patches

Massimo Dal Zotto <dz(at)cs(dot)unitn(dot)it> writes:
> Two small patches:
> 1) make default NBuffers = DEF_MAXBACKENDS*2 as required by check in
> PostmasterMain().

I had proposed moving NDBUFS into config.h and fixing the default a few
days ago, but then forgot to do it. As things stand, if you increase
DEF_MAXBACKENDS at configure time, you'll get a postmaster that won't
start unless you give it a -B setting larger than default. This is bad,
and I agree with Massimo that we ought to make sure the default NBuffers
is one that will work with the default MaxBackends.

This patch is not quite right though, since it doesn't account for the
other part of PostmasterMain's condition (NBuffers >= 16). Will fix.

> 2) check for QueryCancel in the copy command. Maybe we should do the
> same in vacuum command (Vadim?).

I'm not too excited about adding QueryCancel support so soon before the
release, but the part of your patch that you didn't mention (diking out
the "file_opened" hack) is really a critical fix --- as the code stood
it would try to fclose() the same stdio file twice, which is disastrous
in most stdio libraries. I applied that part of it... good catch!

regards, tom lane