Subject: Re: [vserver] Bug or daydreaming: no sched_hard, but still only 1/4th?
From: Herbert Poetzl <herbert@13thfloor.at>
Date: Fri, 29 May 2009 12:56:34 +0200

On Fri, May 29, 2009 at 10:08:40AM +0200, Markus Fischer wrote:
> Hi,
> 
> first, I think I'm daydreaming, however I don't understand what I may be 
> doing wrong.

> I'm running four vservers and lately, since I started more development 
> stuff, noticed they only run 1/4th of the available CPU. The typical 
> default when SCHED_HARD is enabled.

1:4 is the default ratio a guest is assigned

> However I've neither SCHED_HARD enabled, nor defined any sched/* limits.

I'm pretty confident somebody/something does enable the hard
scheduler on guest startup :)

> But I was able to get a 1/1 ratio by *manually* with vsched and now have 
> to use my custom script to set a vserver to 1/1 after launch.

> Ok, if you read the version numbers you'll probably so "it's a bug in 
> that version and you need to upgrade" because I guess they're clearly 
> outdated. But could that be true?

I do not remember such a bug, but the kernel name suggests
that it is a distribution kernel, so it could contain
unknown modifications ....

> I won't upgrade the kernel on the existing system, too high is the risk 
> to break anything. Once I get my new hardware in the next months, I 
> swear I will ...

> Versions:
>                    Kernel: 2.6.18-4-vserver-k7
>                    VS-API: 0x00020002
>              util-vserver: 0.30.204; Dec 20 2005, 16:58:50

that is ancient :)

if you really want to figure that out (I doubt it)
you have to hire somebody to look into that specific
kernel and util-vserver version (and maybe your system
or scripts) or alternatively do that yourself ...

best,
Herbert

> Features:
>                        CC: gcc, gcc (GCC) 3.3.5 (Debian 1:3.3.5-13)
>                       CXX: g++, g++ (GCC) 3.3.5 (Debian 1:3.3.5-13)
>                  CPPFLAGS: ''
>                    CFLAGS: '-Wall -g  -O2 -std=c99 -Wall -pedantic -W'
>                  CXXFLAGS: '-g -O2 -ansi -Wall -pedantic -W 
> -fmessage-length=0'
>                build/host: i386-pc-linux-gnu/i386-pc-linux-gnu
>              Use dietlibc: yes
>        Build C++ programs: yes
>        Build C99 programs: yes
>            Available APIs: compat,v11,v13,fscompat,net,oldproc,olduts
>             ext2fs Source: e2fsprogs
>     syscall(2) invocation: fast
>       vserver(2) syscall#: 273/glibc
> 
> Paths:
>                    prefix: /usr
>         sysconf-Directory: /etc
>             cfg-Directory: /etc/vservers
>          initrd-Directory: $(sysconfdir)/init.d
>        pkgstate-Directory: /var/run/vservers
>             Kernelheaders: /usr/include
>           vserver-Rootdir: /var/lib/vservers
> 
> thanks,
> - Markus