[DRBD-user] Very slow sync speed

Lars Ellenberg Lars.Ellenberg at linbit.com
Mon Jul 25 14:29:55 CEST 2005

Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.

/ 2005-07-25 11:24:50 +0200
\ Wienke Giezeman:
> I have set up a Linux-HA configuration on two systems. DRBD is working, but 
> the speed is very low. It never exceeds 500 Kb. Although I've set rate in 
> drbd.conf to 700000

try to set the sync rate more into the range you actually
expect from your hardware, maybe that helps.

and just check the obvious:

what does hdparm say about your disks?
dma enabled?
hdparm -t -T /dev/whatever ?

hackish benchmark for poor people:
right# netcat -l -p 7777 | time dd of=/dev/somewhere bs=4k count=1234567 ; time sync
 left# dd if=/dev/whatever bs=4k count=1234567 | netcat right 7777

is anything else accessing (seeking on) the physical disk?



: Lars Ellenberg                                  Tel +43-1-8178292-0  :
: LINBIT Information Technologies GmbH            Fax +43-1-8178292-82 :
: Schoenbrunner Str. 244, A-1120 Vienna/Europe   http://www.linbit.com :
please use the "List-Reply" function of your email client.

More information about the drbd-user mailing list