On Sun, Jul 15, 2012 at 5:14 PM, Simon Sapin <simon.sa...@exyr.org> wrote: > Le 14/07/2012 06:07, Graham Dumpleton a écrit : > >>>> >>2. Is the socket FD the same mechanism like nginx? If you upgrade >>>> >> nginx >>>> >>binary, restart nginx, the existing http connection won't break. >> >> I would be very surprised if you could upgrade nginx, perform a >> restart and preserve the HTTP listener socket. If you are talking >> about some other socket I don't know what you are talking about. >> >> As you can with Apache, you can likely enact a configuration file >> change and perform a restart or trigger rereading of the configuration >> and it would maintain the HTTP listener socket across the >> configuration restart, but an upgrade implies changing the binary and >> I know no way that you could easily persist a HTTP listener socket >> across to an invocation of a new web server instance using a new >> executable. In Apache you certainly cannot do it, and unless nginx has >> some magic where the existing nginx execs the new nginx version and >> somehow communicates through open socket connections to the new >> process, I very much doubt it would as it would be rather messy to do >> so. > > > I think that est refers to this: > http://wiki.nginx.org/CommandLine#Upgrading_To_a_New_Binary_On_The_Fly > > Apparently yes, there is specific code in nginx to start the new binary and > give it the existing socket. > > And I think that yes, Tarek’s new Circus is similar to the nginx magic > upgrade in that an open socket is passed around processes. Maybe nginx even > does this in normal operation with multiple worker processes, but I don’t > know. > > Regards, > -- > Simon Sapin Gunicorn does upgrade itself using the USR2 signal just like nginx and share the socket like using an fd between OS processes.
However the case of a db is a little different since you handle a connection to a db and not listening on a port. You will need either a multiprocess queue passing messages to one process or launching a connection per processes. You can do that using the hook system of gunicorn. - benoît _______________________________________________ Web-SIG mailing list Web-SIG@python.org Web SIG: http://www.python.org/sigs/web-sig Unsubscribe: http://mail.python.org/mailman/options/web-sig/archive%40mail-archive.com
