From: vs_list_at_ezpi.net
Date: Thu 23 Jan 2003 - 21:24:18 GMT
Well, this brings me to another question,
How hard would it be to implement a per context time differense compared
to systemwide clock.
Thus a vserver could respond to ALL application including cron etc, that
a server is under EST or CET or whatever,
As well as putting a slight delay (5-30 seconds) between every vserver
to reduce this 04:05 system halt :)
Regards
/Andreas
-----Original Message-----
From: Jacques Gelinas [mailto:jack_at_solucorp.qc.ca]
Sent: den 23 januari 2003 22:12
To: vserver_at_solucorp.qc.ca
Subject: re: [vserver] How many vhosts i can run on one vserver?
On Thu, 16 Jan 2003 16:18:01 -0500,
=?iso-8859-2?Q?Marcin_Sucho=BFebrski?= wrote
> Hello,
>
> I didn't see in docs any number (max numer) of virtual server to run
> on one phisical computer. Which limitations (ex. file handlers,
> devices number) are the lowest and decide on the maximum numer of
> running vservers?
>
> I'll be numer of 200, 500, 1000? We can take situation that i have
> enough resources (CPU, memory, disks)..
>
> I think it will be about 240-250?
A vserver does not use any resource by itself. There is no "invisible"
overhead for each vserver. The overhead comes from the tasks you are
running inside the vserver. In general a vserver will run minimally
syslogd
crond
and sometime
sshd
So this is the overhead. Now each vserver will do something useful. Run
apache or run mysql for example. Running a task inside a vserver uses
the same resources as running it outside (a vserver).
Memory wize, because of the unification, most task will be sharing the
text (program code), so this is fairly efficient.
Now you may want to run very specialised vservers, potentially running a
single task without cron and syslog. So goes down the overhead.
For sure it also depends on the activity of the services. The real issue
is probably there. If you run 50 vservers each running apache and taking
enough hit, you may have performance problem.
Anyway, you will have to try. All I can say is that vserver do not use
resource by itself. It only depends on the apps you are running inside
and they are using the same resources inside or outside a vserver.
Hope this helps.
PS: If you run cron on redhat distro, before of task like updatedb. With
10 vservers they will all wake up at 4 in the morning. The load will go
up. You may want to disable this.
---------------------------------------------------------
Jacques Gelinas <jack_at_solucorp.qc.ca>
vserver: run general purpose virtual servers on one box, full speed!
http://www.solucorp.qc.ca/miscprj/s_context.hc