On 01.03.2006, at 12:56, Rudolf Cejka wrote:
Sebastian Stark wrote (2006/03/01):
I never get more than ~28MB/s backing up to an HP Ultrium-3 drive. I
Momentary speed or overall speed including data spooling, tape write
and database update? For momentary it is slow, for overall it is
relatively fast.
I measured with iostat -x because the speed measured by bacula does
reflect more then just tape I/O. So these 28MB/s are tape write
performance, excluding network/disk/database overhead.
Overhead included I get something around 5-10 MB/s usually.
configured spooling to a locally attached raid that allows for much
faster througput, bonnie++ says ~160MB/s when reading block-wise.
Could this be a problem with my bacula configuration or rather a
problem with my OS configuration? Maybe because both, thhe disk used
for spooling and the tape drive are sharing the same FibreChannel
bus?
It is hard to say. The another reason would be slow processor
or slow machine at all.
It's not NEAR a load of 1 (dual Sparc) and if I query the bacula
database manually it's blazingly fast.
Could it be because I'm using LTO-2 cartridges?
Yes, if you use LTO-2 cartridges, you can get max. LTO-2 speeds.
Then 28MB/s looks pretty good, right? 30 is the most you can get out
of LTO-2 cartridges if I remember correctly.
Thanks for your reply.
-------------------------------------------------------
This SF.Net email is sponsored by xPML, a groundbreaking scripting language
that extends applications into web and mobile media. Attend the live webcast
and join the prime developer group breaking into this new coding territory!
http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642
_______________________________________________
Bacula-users mailing list
Bacula-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/bacula-users
