View Full Version : multiple configurations is slow

November 14th, 2006, 06:46 AM

I am trying to run 4 simultaneous configurations backing up to 1 library with 4 drives using 2.5.1p1.
I am backing up local disks without using a holding disk, but spanning multiple tapes.
The setup works fine for 2 concurrent configurations, running close to the native dump speed, but when I add a 3rd configuration the throughput halves for all running backups.

Any suggestions as to what could be wrong here?



November 14th, 2006, 10:41 AM
Current Amanda versions do not allow drives and slots to be shared between Amanda configurations. You will have to also schedule the backup runs (amdump (http://wiki.zmanda.com/index.php/Amdump)) so that the backup windows from different configurations do not overlap.

What changer are you using?


November 14th, 2006, 10:42 AM
Regarding performance, please provide amreport outputs from both cases.

Please provide the values used for runtapes, tape_splitsize, fallback_splitsize, and split_diskbuffer in amanda.conf for all configurations.


November 14th, 2006, 03:05 PM
Hi Paddy,

Thanks for replying.

I'm using a Sun L40 with DLT 4 drives and 40 slots
Each configuration is setup to use a different drive and a different set of slots in the library (only problem with that is when any two conf's are trying to access the one robot through chg-zd-mtx at the same time )

Apart from that all the configuration parameters are all identical:

runtapes 3
fallback_splitsize 128m
tape_splitsize 2 Gb
split_diskbuffer "/dumps/amanda/live1/split_diskbuffer"

(location of the split_diskbuffer points to 4 different locations: live2, live3 and live4 for the other conf's)