[OpenAFS] cpu load

sabah sabah@hep.man.ac.uk
Tue, 18 Nov 2003 21:48:45 +0000 (GMT)


 Hi Steven,
            Thank you so much. 

On Tue, 18 Nov 2003, Jenkins, Steven wrote:

> 
> Without knowing any details of your system, from your description, it
> appears that the software raid daemons are accounting for your CPU time.
> 
> Without knowing how you've configured your disks (ie, devices,
> controllers, virtual devices, filesystems, mount points), I'd think it
> reasonable for your system, which is a fileserver (I'm assuming), to be
> spending a lot of time doing software raid.  I'd also like to know:

/dev/md0              7.7G  6.2G  1.1G  85% /
/dev/hda1              99M   16M   77M  17% /boot
none                  251M     0  251M   0% /dev/shm
/dev/md1              484M  149M  311M  33% /usr/vice/cache
/dev/md4               97G   33G   60G  35% /vicepg
/dev/md3              2.9G   33M  2.7G   2% /viceph
/dev/md2              2.9G   33M  2.7G   2% /vicepi
/dev/hdg1             113G   73G   34G  68% /bkupdsk
AFS                   8.6G     0  8.5G   0% /afs

This is a copy of raidtab file
-------------------------------------------------------------------------
raiddev             /dev/md0
raid-level                  1
nr-raid-disks               2
chunk-size                  64k
persistent-superblock       1
nr-spare-disks              0
    device          /dev/hda3
    raid-disk     0
    device          /dev/hdc3
    raid-disk     1
raiddev             /dev/md1
raid-level                  1
nr-raid-disks               2
chunk-size                  64k
persistent-superblock       1
nr-spare-disks              0
    device          /dev/hda6
    raid-disk     0
    device          /dev/hdc6
    raid-disk     1
raiddev             /dev/md4
raid-level                  1
nr-raid-disks               2
chunk-size                  64k
persistent-superblock       1
nr-spare-disks              0
    device          /dev/hda8
    raid-disk     0
    device          /dev/hdc8
    raid-disk     1
raiddev             /dev/md3
raid-level                  1
nr-raid-disks               2
chunk-size                  64k
persistent-superblock       1
nr-spare-disks              0
    device          /dev/hda7
    raid-disk     0
    device          /dev/hdc7
    raid-disk     1
raiddev             /dev/md2
raid-level                  1
nr-raid-disks               2
chunk-size                  64k
persistent-superblock       1
nr-spare-disks              0
    device          /dev/hda5
    raid-disk     0
    device          /dev/hdc5
    raid-disk     1
--------------------------------------------------------------------

> 
> - is your system is doing anything else besides serving AFS
 No
> - how many clients does your system have
 90
> - are people doing I/O intensive work on files that reside on your
> fileserver

  not always

> - are there any known issues with your combination of OS & raid software
> 
  I am not aware of any.

> For example, if there are many clients simultaneously doing lots of
> compiles of files in AFS, all of which are on this server, then it might
> be perfectly reasonable to see CPU utilization like you are seeing.

  Is this mean even if I remove software raid. Users can not do lots of
  compiles of files in AFS?


  Many thanks,  Sabah.

> 
> Steven
> 
> -----Original Message-----
> From: openafs-info-admin@openafs.org
> [mailto:openafs-info-admin@openafs.org] On Behalf Of sabah
> Sent: Tuesday, November 18, 2003 2:18 PM
> To: openafs-info@openafs.org
> Subject: [OpenAFS] cpu load
> 
> 
>  Dear All,
>           I have an AFS server running linux.
> "
> Linux version 2.4.18-3 (bhcompile@daffy.perf.redhat.com) (gcc version
> 2.96 
> 20000731 (Red Hat Linux 7.3 2.96-110)) #1 Thu Apr 18 07:37:53 EDT 2002 "
> If one run "uptime" you get
> 
> uptime
>   7:15pm  up 11:11,  2 users,  load average: 2.36, 2.59, 2.66
> 
> Most of the load used by:
>  26 root      16   0     0    0     0 RW   32.0  0.0 161:09 raid1d
>  27 root      15   0     0    0     0 DW   11.5  0.0  67:12 raid1syncd
> 
>  does anyone know how to get the load down please?
> 
>  Thanks,  Sabah.
> 
> 

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