Description of problem: sendmail in FC wakes up every 5 seconds, even when it's totally unused/idle. (It wakes up quicker if a signal comes in about actual mail). The attached patch changes this so that it'll sleep for 30 seconds at a time if it has been idle for 50 seconds continously. This came up during the idle-tick work on the kernel, where we're trying to remove any and all unneeded wakups of the system (first of all the timer interrupt, but that is not enough; all of userland also has a wakeup rate of about 30 per second so we're killing those off one at a time).
Created attachment 135282 [details] patch to sendmail to increase the timeout on idle
Sendmail upstream has rejected this patch: "Then a signal will take up to 30s to have an effect. That doesn't seem like a good idea."
If that is a concern, the usual pipe approach can be used to work around it, no ?
also if they care they can use other mechanisms like sending a sighup etc etc.
One thing that sendmail seems to be doing over and over is re-reading /proc/loadavg It does this to throttle itself if the system gets too busy. There's no point in doing this however if the mail queue is empty. The box I just tested this on recieves no mail, and sends just one per day (logwatch), so this is just pointless work done billions of times a day, for nothing.
Based on the date this bug was created, it appears to have been reported against rawhide during the development of a Fedora release that is no longer maintained. In order to refocus our efforts as a project we are flagging all of the open bugs for releases which are no longer maintained. If this bug remains in NEEDINFO thirty (30) days from now, we will automatically close it. If you can reproduce this bug in a maintained Fedora version (7, 8, or rawhide), please change this bug to the respective version and change the status to ASSIGNED. (If you're unable to change the bug's version or status, add a comment to the bug and someone will change it for you.) Thanks for your help, and we apologize again that we haven't handled these issues to this point. The process we're following is outlined here: http://fedoraproject.org/wiki/BugZappers/F9CleanUp We will be following the process here: http://fedoraproject.org/wiki/BugZappers/HouseKeeping to ensure this doesn't happen again.
This bug has been in NEEDINFO for more than 30 days since feedback was first requested. As a result we are closing it. If you can reproduce this bug in the future against a maintained Fedora version please feel free to reopen it against that version. The process we're following is outlined here: http://fedoraproject.org/wiki/BugZappers/F9CleanUp