Re: New socket code for win32 - Mailing list pgsql-patches

From Bruce Momjian
Subject Re: New socket code for win32
Date
Msg-id 200404110145.i3B1j5w29478@candle.pha.pa.us
Whole thread Raw
In response to Re: New socket code for win32  ("Magnus Hagander" <mha@sollentuna.net>)
List pgsql-patches
Your patch has been added to the PostgreSQL unapplied patches list at:

    http://momjian.postgresql.org/cgi-bin/pgpatches

I will try to apply it within the next 48 hours.

---------------------------------------------------------------------------


Magnus Hagander wrote:
> I have been running with this patch for a week now, and it is more
> stable than what's in there now for me. So I think it's ready to go.
>
> I have attached an updated socket.c file that changes the following:
> * Corrects two incorrect comments
> * Zeroes out the fd_sets in select at EINTR for consistency
>
>
> //Magnus
>
>
> >-----Original Message-----
> >From: Magnus Hagander
> >Sent: den 4 april 2004 22:08
> >To: pgsql-patches@postgresql.org
> >Subject: [PATCHES] New socket code for win32
> >
> >
> >Here's an attempt at new socket and signal code for win32.
> >
> >It works on the principle of turning sockets into
> >non-blocking, and then
> >emulate blocking behaviour on top of that, while allowing signals to
> >run. Signals are now implemented using an event instead of APCs, thus
> >getting rid of the issue of APCs not being compatible with "old style"
> >sockets functions.
> >
> >It also moves the win32 specific code away from pqsignal.h/c into
> >port/win32, and also removes the "thread style workaround" of the APC
> >issue previously in place.
> >
> >In order to make things work, a few things are also changed in
> >pgstat.c:
> >
> >1) There is now a separate pipe to the collector and the bufferer. This
> >is required because the pipe will otherwise only be signalled in one of
> >the processes when the postmaster goes down. The MS winsock code for
> >select() must have some kind of workaround for this behaviour, but I
> >have found no stable way of doing that. You really are not supposed to
> >use the same socket from more than one process (unless you use
> >WSADuplicateSocket(), in which case the docs specifically say that only
> >one will be flagged).
> >
> >2) The check for "postmaster death" is moved into a separate select()
> >call after the main loop. The previous behaviour select():ed on the
> >postmaster pipe, while later explicitly saying "we do NOT check for
> >postmaster exit inside the loop".
> >The issue was that the code relies on the same select() call
> >seeing both
> >the postmaster pipe *and* the pgstat pipe go away. This does not always
> >happen, and it appears that useing WSAEventSelect() makes it even more
> >common that it does not.
> >Since it's only called when the process exits, I don't think using a
> >separate select() call will have any significant impact on how
> >the stats
> >collector works.
> >
> >
> >
> >Anyway. Here is a patch for review. The two files go in
> >backend/port/win32/.
> >
> >Passes all regression tests expected (time and ordering ones still
> >fails, pgstat works)
> >
> >//Magnus
> >
> >

Content-Description: socket.c

[ Attachment, skipping... ]

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