On Thu, 31 Aug 2006, W B Hacker wrote: > Bodo Gelbe wrote: > >> I've the following problem with exim and exiscan: >> >> Exim calls spamd in the DATA ACL (for messages from >> external hosts). >> >> spamassassin/spamd is configured with >> >> bayes_auto_learn 1 >> bayes_journal_max_size 0 >> bayes_auto_expire 0 >> bayes_learn_to_journal 1 >> >>> From time to time (cronjob) the database and the journal are >> synchronized (sa-learn --sync). During the synchronization >> process SMTP requests are hanging for 20 to 50 seconds (even >> those from local hosts, which will not be scanned by spamd). >> Number of exim processes are increasing. > > Does 'exiwhat' confirm that local traffic is in the pile of slowed-down > processes? Does it tell you anyhting else that might be useful?
shows an increasing number of processes with status "handling incoming connection from ..." > > What is CPU/memory load at the time? Low. > >> >> Looks like something is locked within exim before spamd >> is called, which locks out processing for messages not >> undergoing spamd processing. >> > > May be that those that *are* awaiting SA have used up enough resources, > limits, > that the others are simply awaiting earlier processes to finish? I've tried a "sendmail -d+all ..." during bayes sync and it shows two delays: 08:32:05 3749 Date: Fri, 01 Sep 2006 08:32:05 +0200 08:32:05 3749 08:32:13 3749 Data file written for message 1GJ2ZR-0000yT-OK 08:32:13 3749 Writing spool header file 08:32:40 3749 Size of headers = 278 seems something in the spool area is locked before the call to exiscan and exiscan is waiting for the lock of the bayes databases to be released -> processing of the incoming message stucks. > > Are your various limits all at default, or? > >> Any idea how to avoid the delay (dont't want a transport >> because we're doing greylisting based upon the spam level)? >> >> kr, Bodo >> > > Changing the scheduled sync to low-load time-of-day, or providing greater > resources aside, I'll suggest a contrarian approach: > > - Check and see how many times has the Bayes point contribution to the total > SA > score been sufficiently high to 'tip the balance' when a given message was not > *already* firmly tagged as Spam by other rules, OR deniable for protocol, > invalid recipient/domain, format, attachment, MIME, viral reasons? > > Hint: In the as-issued SA, most Bayes scores are so miniscule they rarely > contribute enough to matter, yet Bayes consumes significant resources. > > Worse - Bayes on a server where user traffic can be so very different, one > from > another, seems to get confused far more easily than when run on an individual > user's MUA. (pays its way on Mozilla/Thunderbrd and others...) > > Server-side, we've shut Bayes off entirely with more beneficial results than > not. > > Greylisting, BTW, is likely to more than double your connection load, (retry > may > be idioticlly rapid for zombies) - spawning child processes that may not go > all > the way through to the DATA phase, but will certainly consume resources. Yes but we're using greylisting only for selected mailboxes. > > Might help to run 'queue_only', adjust your queue runner interval 'til the > resources balance better. Some users are complaining because of the pause during the SMTP session. They're using pine with SMTP support (not sendmail). It's not a resource problem. From my point of view it's a problem with setting/releasing locks. > > YMMV, > > Bill kr, Bodo -- ## List details at http://www.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://www.exim.org/eximwiki/
