[DRBD-user] Sync its so slow

Igor Neves igor at 3gnt.net
Tue Oct 23 19:39:10 CEST 2007

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


Hi,

I'm having problems with sync, using drbd 8.0.4, in centos 5.0.

When i have to do one full sync, of the disc, it takes me 12 Hours
(500G).

The 2 nodes are connected between Gigabit Ethernet, my question it's,
what do i have to do, to make it faster? This time is insane! :)

I know my disk does not write at Gigabit ethernet capacity, but indeed,
lets say it writes at least at 50MBytes/sec.

If we write data, at 50MBytes/sec it should take theoretically about
1.66 hours, its about 1h and 40 minutes or so.

Of course the disk writes faster than that, at least in this case i
have one SAS controller with 15k rpm disk's.

I have in drbd.conf configured 'rate 100M'.

I have drbd over the disk, and ext3 over it, but i think this is
transparent for drbd, this should not take the drbd to slow.

When it is doing the full sync, i see in '/proc/drbd' and it says it's
copying at about 20K/sec, and since it is in bits, it is pretty slow.

This is bug? Or I am the bug? :) Since I'm new to drbd, i think the
second option will be more likely then the first one! :D

Gigabit Ethernet = 125MBytes/Sec

Thanks for all the help.
---------
Igor Neves <igor.neves at 3gnt.net>
3GNTW - Tecnologias de Informação, Lda
 
 sip igor at 3gnt.net 	jid igor at jabber.3gnt.org
 icq 249075444		tlm 00351914503611




More information about the drbd-user mailing list