I am not sure if you could easily tell when a process is hung. IMAP processes at least can be remarkably persistant. For example, we have some users with cable or DSL connections at home. If these folks leave an email client open and it checks for mail with a period that is shorter than the idle time out, they can keep the same IMAP process for weeks.
In a MTA like postfix, if a delivery process hangs around for more than a few minutes, you can be sure it is hung up. In an imap server we could probably do this kind of checking on lmtpd's and pop3d's, bu I think it would be really tricky to do for imapd's. Also with process reuse in 2.x , it seems like it would be much harder. That being said, more power to you if you can do it. John Wade Henrique de Moraes Holschuh wrote: > On Tue, 16 Apr 2002, John Wade wrote: > > Hi seen file lock suffers, > [...] > > to my patch to work around seen file locking issues in cyrus 2.0.16 and > > 2.1.3. For those who have already installed it, there are no changes in > [...] > > The patch is interesting, and I would apply it just-in-case to the Debian > code, but I think we have room in cyrus for a more general solution. > > I'd like to see watchdogs in cyrus, just like we have in postfix for > example. That would protect us of all bugs like the hanging imap and pop3d > from causing resource starvation, while we track down and fix whatever issue > is causing the subsystem to hang... > > Are there any ongoing efforts to do so? If not, I probably can start working > on something like this (probably borrowing code from postfix, as soon as I > am able to verify if the licenses of both cyrus and postfix would not cause > trouble). > > What does the CMU crew think of this idea? > > -- > "One disk to rule them all, One disk to find them. One disk to bring > them all and in the darkness grind them. In the Land of Redmond > where the shadows lie." -- The Silicon Valley Tarot > Henrique Holschuh
