On Wed, 10 Oct 2007, Rob Mueller wrote:
I think the problem at the moment is that the process you really want is:
1. Stop new imap/pop/lmtp/sieve/etc connections
2. Finish and close existing connections cleanly but as quickly as possible
3. Finish running any sync log files
4. Fully shutdown
There's currently no clean way to do this. Basically you have to SIGTERM
master which hard kills it and all children, then manually run
sync_client -f on any remaining log files.
This would seem to be a significant advantage of running sync_client
outside master.
When I shut down master, sync_client continues to process the outstanding
log. I can then use sync_shutdown_file when it has finished and is idle.
sync_client could catch SIGQUIT to initiate some form of clean shutdown.
I'm still a little bothered about signal handling and EINTR. I did some
experiments after our last chat about signals. In practice disk IO system
calls seem to be reasonably safe against EINTR on both Linux and Solaris,
but a trip to Google suggests that there are few guarantees:
http://archives.postgresql.org/pgsql-hackers/2005-12/msg01259.php
There seems to be a spilt of opinion between BSD and SVR4: BSD tries to
retry while SVR4 throws EINTR. Linux of course can work either way:
http://www.gnu.org/software/libc/manual/html_node/Interrupted-Primitives.html
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David Carter Email: [EMAIL PROTECTED]
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