Re: rename/unlink handling for Win32

Oh, one more thing.  dirmod.c has Win32 source to show the actual hangs
caused by rename/unlink --- just define TEST_VERSION and compile.  If
someone wants a binary, let me know.

And sorry I posted to hackers rather than patches, where it belongs.

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

Bruce Momjian wrote:
> Here is my approach to the use of rename/unlink on Win32.  The full
> discussion is at:
> 
>     http://momjian.postgresql.org/cgi-bin/pgtodo?win32
> 
> Basically, rename/unlink will fail if the file is opened.  You can move
> the open file to another name, but that then requires open to loop in
> case the file is missing.
> 
> The following patch loops over rename/unlink every 1/10th of second,
> printing a warning message after 1 second, and printing a completion
> message if a warning message was printed.
> 
> I looked at PeerDirect's and SRA's port, and neither provides a better
> method.  I looked at PeerDirect's and it actually has some conditional
> code for rename.  For example, it has a signal that is sent to all
> backends to inform them to close their open WAL files.  I am not sure if
> that is required for us because there is some replication stuff in
> there that we aren't using. Jan?  In a few other places, it allows the
> rename to fail.
> 
> I am inclined to implement it as shown, then see what delayed
> rename/unlinks we get in testing.

--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
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