Control: reassign -1 systemd On Sat, Apr 20, 2019 at 04:30:24AM +0000, Boylan, Ross wrote: > Package: apt > Version: 1.4.9 > Severity: normal > > Dear Maintainer,
It would be nice to include a bug description here (even if it's just repeating the subject). Let me do that: The problem is that the timer adds random time every 5 seconds. > > Severity note: This appears to be relatively trivial problem in its impact > on the system. However, it has two possible more serious consequences: > 1. The logs will end up taking a lot of space because of the constant messges. > 2. The repeated randomization may end up producing really wild random numbers, > as a result of which the timers may fire either way too fast or way too slow. > > The log spam also makes it more difficult to identify interesting things in > the log (I know > there are ways around that), and the whole process must impose some > performance penalty. > > * What led up to the situation? > After a recent upgrade to stretch, my logs are filled with messages like this > Apr 19 12:38:27 ross-mail systemd[1]: apt-daily.timer: Adding 9h 57min > 34.907602s random time. > Apr 19 12:38:27 ross-mail systemd[1]: apt-daily-upgrade.timer: Adding 51min > 17.211953s random time. > Apr 19 12:38:32 ross-mail systemd[1]: Time has been changed > Apr 19 12:38:32 ross-mail systemd[1]: apt-daily.timer: Adding 11h 36min > 18.852889s random time. > Apr 19 12:38:32 ross-mail systemd[1]: apt-daily-upgrade.timer: Adding 7min > 19.203357s random time. > Apr 19 12:38:37 ross-mail systemd[1]: Time has been changed > Apr 19 12:38:37 ross-mail systemd[1]: apt-daily.timer: Adding 11h 4min > 53.484274s random time. > Apr 19 12:38:37 ross-mail systemd[1]: apt-daily-upgrade.timer: Adding 4min > 43.246953s random time. > Apr 19 12:38:42 ross-mail systemd[1]: Time has been changed > Apr 19 12:38:42 ross-mail systemd[1]: apt-daily.timer: Adding 6h 27min > 36.345186s random time. > Apr 19 12:38:42 ross-mail systemd[1]: apt-daily-upgrade.timer: Adding 15min > 43.087263s random time. > Apr 19 12:38:47 ross-mail systemd[1]: Time has been changed > Apr 19 12:38:47 ross-mail systemd[1]: apt-daily.timer: Adding 4h 46min > 3.780698s random time. > Apr 19 12:38:47 ross-mail systemd[1]: apt-daily-upgrade.timer: Adding 2min > 25.572155s random time. > Apr 19 12:38:52 ross-mail systemd[1]: Time has been changed > Apr 19 12:38:52 ross-mail systemd[1]: apt-daily.timer: Adding 6h 54min > 42.591556s random time. > Apr 19 12:38:52 ross-mail systemd[1]: apt-daily-upgrade.timer: Adding 18min > 42.538730s random time. > Apr 19 12:38:57 ross-mail systemd[1]: Time has been changed > Apr 19 12:38:57 ross-mail systemd[1]: apt-daily.timer: Adding 40min 9.786990s > random time. > repeating endlessly. > > The system is running under HyperV, which I gather resets the clock every 5 > seconds. > > * What exactly did you do (or not do) that was effective (or > ineffective)? > Searching turned up Debian bug 600262, which sounds similar. However, the > solution > to it was to switch to the systemd timer, which seems to be source of the > current problem. > > https://askubuntu.com/questions/888493/var-log-syslog-systemd1-time-has-been-changed-message-every-5-seconds/890354#890354?newreg=0c5a628a4d8a4809a9298176c94d004e > reports a similar problem. The top-rated solution is to disable the time > update in HyperV. Apart from the fact that I lack > the necessary rights, this seems liable to cause clock drift. > > An alternate solution is to modify the filters for the log file to keep out > the messages. > This is probably what I'll do, though I'm not sure the mechanics are is given > there. > The suggestion modified /etc/rsyslog.d/, and I thought systemd was now doing > the logging. > > The same alternate solution says another alternative is to disable host time > sync on VMBUS. > It's not explained, and once again completely breaking the connection seems > extreme. > > * What was the outcome of this action? > Nothing done yet. If I succeed in quieting the log, I'll still have the > repeated timer updates. > I do not know if the repeated random times are additive, or simply replace > the previous one. > In the former case, the effects seem likely to be bad. E.g., if the times > added accumulate, > the timer may never fire. > > * What outcome did you expect instead? > I would like for my VM time to remain syncronized with the host, > for my log not to be filled a huge number of junk messages, > and for the random timers to be reset just once. > There's nothing we can do here in apt. Now, maybe systemd should not log that excessively or not adjust its timers for miniscule time changes. -- debian developer - deb.li/jak | jak-linux.org - free software dev ubuntu core developer i speak de, en
