On ons, 2012-05-30 at 23:43 +0200, Tomas Vondra wrote: > On 30.5.2012 23:19, Tom Lane wrote: > > I suspect it depends on how you install the new version of the library, > > too. I would somewhat expect it to work as you're thinking if the > > install consists of "rename old file out of the way, copy new file into > > place, unlink old file" or equivalent. If you are actually > > *overwriting* the file in place, a crash does not seem especially > > surprising --- it would make perfect sense if the kernel expects the > > file to be usable as backing store for the in-memory image, which is not > > exactly unreasonable. IOW, if the in-memory bits we're executing are > > just an mmap'd image of the .so file, changing the .so file could > > entirely be expected to lead to a crash. > > Aha! That might be the culprit - I've just tested that deleting the olf > file and copying new version (thus not overwriting it) did not cause a > crash. Funny.
That's one of the reasons why one normally uses "install" rather than "cp" to install files. So this shouldn't be a problem in practice if people use the provided pgxs infrastructure or something similar. GNU cp has the --remove-destination option, which should also work for this purpose. -- Sent via pgsql-bugs mailing list (pgsql-bugs@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-bugs
