This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
Home Products Support Community News


[Xen-users] poor network performance?

To: xen-users@xxxxxxxxxxxxxxxxxxx
Subject: [Xen-users] poor network performance?
From: Kirchy <kirchy@xxxxxx>
Date: Tue, 28 Jun 2005 20:42:47 +0200
Delivery-date: Tue, 28 Jun 2005 18:41:46 +0000
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
List-help: <mailto:xen-users-request@lists.xensource.com?subject=help>
List-id: Xen user discussion <xen-users.lists.xensource.com>
List-post: <mailto:xen-users@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Mozilla Thunderbird 1.0 (X11/20041206)
I played around with Xen before and now wanted to make serious use of it for the first time:

I installed Xen on a p4-2.6ghz, 2GB RAM and SATA-disks (debian linux)
I set up an guest with debian sarge with no problems on a seperate 200gb-partition (as /).

I then tried to copy a large file (300mb) via scp and ftp from my main database-server to the xenU (gigabit network, server is a opteron on a high-end tyan-board with LAN on board, xen-pc is a intel-board with gigabit-lan on board) to have an idea of how long it would take to copy a large backup file via the network, but copying was so slow (around 4MB/sec), that i thought the ethernet-card might be in 100mbit-mode - but it wasn't. I have the same poor performance no matter if I copy to dom0 or domU :( I copied the same file to another database-server in the gigabit-network and got around 12mb/sec (still slow, but that other database is under heavy load so a lot of traffic should be on there) I have acceptable performance when I copy a 300mb-file locally on the xen0 from one sata-disk to another (16mb/sec). (time cp /tmp/file.dat /disk2/file.dat) I have around 9mb/sec if I copy a 300mb-file locally on xenU (time cp file.dat file2.dat) on the same partition

I found out that eth0 on the xen0 was in promiscuous mode (because of xen or the bridge utils?) and disabled that ( ip link set eth0 promisc off), but the speed didn't change.

Any ideas somebody? We've been using that Server with the same hardware before as a backup system and didn't have any performance problems. When I start the server with the standard debian 2.6.7-kernel, I get around 12mb/sec, so it must be about the xen-kernel?

Thanks for any hints... I'm stuck and confused right now..


Xen-users mailing list

<Prev in Thread] Current Thread [Next in Thread>
  • [Xen-users] poor network performance?, Kirchy <=