This one time, at band camp, Simon Josefsson said: > Hi. I'm using clamav-milter on a pretty busy mail server that uses > sendmail (from debian, 8.13.3-6). We have run 'testing' for a long > time, and it has worked well until recently (perhaps a few weeks at > most). Sometimes, in the syslog I get these: > > Feb 25 23:47:53 yxa sm-mta[9481]: j1PMhp23009481: Milter (clamav): timeout > before data read > Feb 25 23:47:53 yxa sm-mta[9481]: j1PMhp23009481: Milter (clamav): to error > state > > And when this happen, I have tons of clamav-milter processes running: > yxa-iv:~# ps auxww|grep clama|wc -l > 196 > > MaxThreads 12 > MaxConnectionQueueLength 15
You have hit MaxThreads/MaxConnectionQueueLength limit. The way this works is there are so many threads (12 in your case), and they each have a queue of requests waiting (15 for you). They each allow MaxConnectionQueueLength of requests to wait before denying any additional. So you can have 12 x 15, or 180 clamav-milter requests hanging around. 196 is over that, so 16 threads timeout waiting for a response. Some experimentation is probably necessary to figure out the ideal for your system, but generally, more threads = more system load, while bigger queue = longer wait times. If you have a really fast processor and a relatively loaded system, you might get this under control by upping the MaxConnectionQueueLength. If you have a system where load is not much of an issue, try upping MaxThreads. My usual first try is upping MaxThreads, as that processes requests fastest. It does bring some load problems with it, though, which is why I mention MaxConnectionQueueLength. This does not sound like a bug to me, so much as a need for performance tuning. If you agree, I would like to close this. If I misunderstood, please let me know what I didn't understand and we can work to fix it. Hope that helps, and if you need more help with performance tuning, please try either the documentation, clamav-users@lists.clamav.net, #clamav on IRC, or myself. Take care, and thanks for reporting, -- ----------------------------------------------------------------- | ,''`. Stephen Gran | | : :' : [EMAIL PROTECTED] | | `. `' Debian user, admin, and developer | | `- http://www.debian.org | -----------------------------------------------------------------
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