Re: [Xen-users] Increasing throughput on xen bridges

[tmac <tmacmd@xxxxxxxxx>]

>From experience, RHEL3 is real bad at performance in general (NFS)

At the lab I work in, my first recommendation was to move to RHEL4U2.
There was almost a 2x performance increase across the network.

As for tuning, I did the following (it only works for 2.6+ kernels though)
on both my Host and guests (all rhel5.1)

The following NFS mount options:
hard,intr,vers=3,tcp,wsize=32768,wsize=32768,timeo=600

Here are the changes to the /etc/sysctl.conf file on the Guests
(for the host, the last line, sunrpc, is not available, so remove it)

net.core.netdev_max_backlog = 3000
net.core.rmem_default = 256960
net.core.rmem_max = 16777216
net.core.wmem_default = 256960
net.core.wmem_max = 16777216
net.core.rmem_default = 65536
net.core.wmem_default = 65536
net.core.rmem_max = 8388608
net.core.wmem_max = 8388608
net.ipv4.tcp_rmem = 4096 87380 4194304
net.ipv4.tcp_wmem = 4096 16384 4194304
net.ipv4.tcp_mem = 4096 4096 4096
sunrpc.tcp_slot_table_entries = 128

Also, add "/sbin/sysctl -p" as the first entry in /etc/init.d/netfs to
make sure that the setrtings get read before any NFS mounts take
place.

For the record, I get 95-102MB/sec each with a simple DD

On Jan 6, 2008 5:36 AM, carlopmart <carlopmart@xxxxxxxxx> wrote:
> Hi all,
>
>   I have a rhel 5.1 xen server with two rhel 3 ES hvm guests installed. Both
> rhel3 guests use an internal xen bridge (xenbr1) which it isn't binded to any
> physical interface host. On this bridge throughput it is very very poor, only
> 2.5 Mbs. How can I increase this throughput???
>
> Many thanks.
> --
> CL Martinez
> carlopmart {at} gmail {d0t} com
>
> _______________________________________________
> Xen-users mailing list
> Xen-users@xxxxxxxxxxxxxxxxxxx
> http://lists.xensource.com/xen-users
>



-- 
--tmac

RedHat Certified Engineer #804006984323821 (RHEL4)
RedHat Certified Engineer #805007643429572 (RHEL5)

Principal Consultant, RABA Technologies
240-373-3926 (office) 301-688-4705 (Lab)
           214-279-3926 (eFAX)

_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users