[DRBD-user] DRBD performance over GBit Ethernet

Andreas Semt as at computer-leipzig.de
Wed Apr 7 21:08:25 CEST 2004

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


Curtis Tiffany wrote:

> I used tiobench and bonnie when testing performance.  The systems sound similar to yours, they are Dell Poweredge 2650, 
> dual Xeon, 5 disk RAID5, 2 GB RAM.  I've attached the output from each... 

first of all: Thanks for the output ... i see I have a real performance
problem somewhere ... bonnie++ gives around 8 MB/s for writing on the
local disks. However the block device for bonnie++ testing was an LVM
Logical Volume. I will testing without LVM. Also I try to "tune" the
Adaptec controller. I will post new information about this topic
tomorrow. Hope to find the problem.

> I used tiobench and bonnie when testing performance.  The systems sound 
> similar to yours, they are Dell Poweredge 2650, dual Xeon, 5 disk RAID5, 
> 2 GB RAM.  I've attached the output from each...
> 
> For drbd-3.htm here's a key
> /home1000c    - testing disk, drbd, and network

You used bonnie on a drbd device and got 25.62 (MB/sec?) for Sequential
Writes and 6.35 (MB/sec?) for Random Writes? That's a good performance.
Tested with tiobench for drbd-3.htm?
> /root1000c    - testing disk without drbd

Why is /root1000c slower (5.22) than /home1000c (6,35) for Random Writes?

Thanks a lot!

To Lars:
Great, i will use the tool tomorrow to find the bottleneck!
Also I've made a new posting to the LVM thread.

To Holger:
> Are the network and disks on a 64-Bit PCI channel and are these working in
> 64 bit mode? 32-bit PCI bus will not manage. But even a 32 bit bus should
> do more then 7MB/s, so something is wrong with your raid5 or network
> card/driver. Are there any messages in /var/log/messages?

Nope, no negative messages at all ... but i will watch ...
The NICs are onboard (Intel GBit) and the network is not the problem
(NetIO with TCP/IP around 100 MB/sec). The disk controller (Adaptec
2110S) is on a PCI X bus, so what? Disks are SCSI U320 10K RPM a 64 GB
capacity. Any hints?

Again: Thanks to all!

Greetings,
Andreas Semt





More information about the drbd-user mailing list