[vserver] load tests for memory

From: Mehdi Bennani <joeytriviano_at_gmail.com>
Date: Wed 17 May 2006 - 09:07:15 BST
Message-ID: <4a1c34ee0605170107x50a5640eyaf04f72c89617acd@mail.gmail.com>

Hello,

As a student, I am making a project about virtualization for dedicated
webservers to be offered to customers.
One important concern is to determinate how many vservers can be
hosted on the same machine, by making load tests.

I have installed collectd and rrd on the host, and one vserver with
apache to serve html pages with processor usage, system load, memory
usage, for the host and the vservers (thanks to the collectd plugin
for vserver and the collectd2html.pl script!).

I have several test vservers with schedule and rlimits, on which I run
memtest to fill completly the memory and see if limitations are
respected and what is system's behavior if total memory rlimits exceed
host's memory.

Is vserver designed to kill processes that try to use more memory than
available on the host system?
I have experienced such behaviour with memtest when total vservers rss
approach total host RAM and trying to start a new memtest on another
vserver:

Allocated 273678336 bytes...trying mlock...Killed

..and cannot determine if memtests exits itself because it cannot lock
pages anymore or if it is killed by the kernel because host RAM is
full?

By the way, I'm not sure memtest is the ideal for what I am trying to
do: fill each vserver allocated memory at its max and see what's
happening, end eventually what happens when swap is starting to be
used, but memtest locks all the pages so swap is never used... Anyone
knows about a more appropriate test software just filling RAM with
loads of data?

Thanks a lot, any help will be welcome.

Mehdi Bennani

=============================================
System info:

Dell 1850 2*Intel Xeon 3Ghz
1G RAM

Debian 3.1 with precompiled 2.6.12lvs kernel and apt-get'ed
util-vserver: 0.30.210

vserver:/# vserver-info
Versions:
                   Kernel: 2.6.12lvs
                   VS-API: 0x00020001
             util-vserver: 0.30.210; Apr 19 2006, 16:06:42
_______________________________________________
Vserver mailing list
Vserver@list.linux-vserver.org
http://list.linux-vserver.org/mailman/listinfo/vserver
Received on Wed May 17 09:07:42 2006

[Next/Previous Months] [Main vserver Project Homepage] [Howto Subscribe/Unsubscribe] [Paul Sladen's vserver stuff]
Generated on Wed 17 May 2006 - 09:07:49 BST by hypermail 2.1.8