Hi Joe or anyone else,
When is Virtualmin Pro set to check for package updates (i.e. yum update)?
The reason for asking is, our server is not operating on US time, and on quite a few occasions we found the server dragging its feet (high CPU utilisation) during the day when traffic is high. I have checked the processes when this happens, and from what I could see it is related to yum update.
Please advise. Thanks.
go into your cron settings and check. Mine are set to 4:02 am and my clock is set to local, not UTC offset.
Thanks Dan.
It seems mine is the same (4:02am local time).
But I noticed the server slowdown associated with yum update during the day (AEST).
Actually, I believe Virtualmin does check for updates periodically during the collectinfo.pl process for the System Information page. I’m not sure whether it happens on every collectinfo.pl run or not. I believe it just does a yum list, which is pretty cheap to do–it definitely doesn’t do a yum update (so if you’re actually seeing an update happening it’s not collectinfo.pl). I guess if you’ve got a lot of repositories configured, or a slow network, it might run for a while.
I’ve just tested, and on my boxes it takes about 4.5 seconds of CPU time, and 5.5 seconds of wall clock time (which accounts for display of the list on a command line, and would probably be about right for the time it takes for Perl to process the list). I have the core OS repos and the Virtualmin repos. Additional repos that have a lot of packages could slow it way down–particularly if those repos are slow.
Thanks Joe! Your explanation helps me to narrow it down further on the possible cause of our server slowdown.
No, our server is not set to do an automatic yum-update, so it is definitely not yum-update.
I have just checked our server (> Webmin > System > Running Processes).
There is a process called yum-updatesd. What is it?
yum-updatesd is a daemon that is enabled when you choose to have automatic updates happen on a Fedora or RHEL or CentOS box (when installing the OS, I believe you’re given the option, but it never mentions yum-updatesd by name). Anyway, it shouldn’t take a lot of resources to have it run. I think even if you aren’t using automatic updates, it’ll run just to find out if updates are available for the updates status bar widget in Gnome (but I might be wrong about that).
Ah, I see. We are running on CentOS 5.
So yum-updatesd is not in any way related to Virtualmin? And Virtualmin does not need it to run smoothly?
Do you think it is OK to disable it?
Our server is hosted at the data centre, and managed solely using Virtualmin Pro (that’s the way we like it, aha aha… 
).
Correct, yum-updatesd has relation to Virtualmin.
It’s fine to disable it, as long as you keep an eye on updates. Virtualmin’s updates module only tells you about hosting related packages–the stuff we depend on (though you can always use the Webmin Software Packages module to update everything with yum). I suspect it’s actually not all that useful on a system without Gnome (since I think it’s primary value is in the notifications it provides on the desktop–one can easily make a cronjob to run “yum -y update” every night and not give up the resources of the updates daemon).
Anyway, short answer is, I don’t know what it does, really, as it isn’t our software!
Roger that, Joe. Thanks.
PS: I think you meant: "Correct, yum-updatesd has NO relation to Virtualmin."
Right. "no" is an important little word.