RE: [Xen-devel] etherbridge bottleneck

["Ian Pratt" <m+Ian.Pratt@xxxxxxxxxxxx>]

David,

You might want to try giving one of your domains a second VIF and then
manually assign an IP address to the vifX.Y interface in domain 0 rather
than using the bridge.  

I doubt the bridge is a serious overhead in xenU<->xenO communication,
but it would be useful to eliminate it from your results.

For high-performance xenU<->xenU communication it probably makes sense
to setup a direct netfront/back connection (to avoid going via the dom0
bridge). Although the netfront/back drivers are quite happy working
point-to-point, I doubt xend will let you set this up right now.
Shouldn't be too hard to fix, though...

Ian

> -----Original Message-----
> From: xen-devel-admin@xxxxxxxxxxxxxxxxxxxxx 
> [mailto:xen-devel-admin@xxxxxxxxxxxxxxxxxxxxx] On Behalf Of 
> David Becker
> Sent: 11 November 2004 14:57
> To: xen-devel@xxxxxxxxxxxxxxxxxxxxx
> Subject: Re: [Xen-devel] etherbridge bottleneck
> 
> 
> " (1) Is Xen running on a UP, SMP or HT?
> 
> all of the above
> 
> " (2) If Xen is running on a SMP or HT, are xen0 and xenU 
> running " different processors or threads?
> 
> xm list doesn't break out HT contexts, so who's to say..
> 
> " (3) Which scheduler in Xen are you using? Have you changed 
> any parameters?
> 
> factory defaults.
> 
> 
> Here is a full account of configs and iperf speeds between 
> domains on an otherwise-idle host via the etherbridge, plus 
> iperf speed over the loopback interface for each domain.
> 
> Uni-processor (PIII)
>         426 Mbps xenU UNI -> xen0 UNI
>         267 Mbps xen0 UNI -> xenU UNI
>         3.34 Gbps xen0 loopback
>         3.14 Gbps xenU loopback
> 
>         xm list
>          Name              Id  Mem(MB)  CPU  State  Time(s)  Console
>          Domain-0           0       34    0  r----    297.0        
>          grant              2      499    0  -b---    161.2    9602
>         xm info
>          system                 : Linux
>          host                   : rack099-xen
>          release                : 2.4.27-xen0
>          version                : #3 Wed Nov 10 11:29:37 EST 2004
>          machine                : i686
>          cores                  : 1
>          hyperthreads_per_core  : 1
>          cpu_mhz                : 1396
>          memory                 : 2047
>          free_memory            : 1485
> 
> slow Uni HT processor (P4 2.0GHz)
>         498 Mbps xenU HT1 -> xen0 HT0
>         369 Mbps xen0 HT0 -> xenU HT1
>         2.49 Gbps xen0 loopback
>         2.54 Gbps xenU loopback
> 
>         xm list
>          Name              Id  Mem(MB)  CPU  State  Time(s)  Console
>          Domain-0           0       34    0  r----    561.7        
>          globus             1      799    1  -b---    225.5    9601
>         xm info
>          system                 : Linux
>          host                   : rack160-xen
>          release                : 2.4.27-xen0
>          version                : #2 Thu Nov 4 15:57:19 EST 2004
>          machine                : i686
>          cores                  : 1
>          hyperthreads_per_core  : 2
>          cpu_mhz                : 1993
>          memory                 : 1023
>          free_memory            : 167
> 
> faster Dual HT processors (P4 2.6GHz)
>         645 Mbps xenU ctxt-1 -> xen0 ctxt-0
>         470 Mbps xen0 ctxt-0 -> xenU ctxt-1
>         782 Mbps xenU ctxt-2 -> xen0 ctxt-0
>         563 Mbps xen0 ctxt-0 -> xenU ctxt-2
>         747 Mbps xenU ctxt-1 -> xenU ctxt-2
>         691 Mbps xenU ctxt-2 -> xenU ctxt-1
>         3.34 Gbps xen0 ctxt-0 loopback
>         3.50 Gbps xenU ctxt-1 loopback
>         3.41 Gbps xenU ctxt-2 loopback
> 
>         xm list
>          Name              Id  Mem(MB)  CPU  State  Time(s)  Console
>          Domain-0           0       34    0  r----   1032.7        
>          batch020           3     1999    1  -b---  108571.9    9603
>          batch040           2     1799    2  r----  154375.3    9602
>         xm info
>          system                 : Linux
>          host                   : rack276-xen
>          release                : 2.4.27-xen0
>          version                : #2 Thu Nov 4 15:57:19 EST 2004
>          machine                : i686
>          cores                  : 2
>          hyperthreads_per_core  : 2
>          cpu_mhz                : 2599
>          memory                 : 3967
>          free_memory            : 94
> 
> 
> -------------------------------------------------------
> This SF.Net email is sponsored by:
> Sybase ASE Linux Express Edition - download now for FREE 
> LinuxWorld Reader's Choice Award Winner for best database on Linux.
> http://ads.osdn.com/?ad_id=5588&alloc_id=12065&op=click
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxxxxxxxxxx
> https://lists.sourceforge.net/lists/listinfo/xen-devel
> 
> 


-------------------------------------------------------
This SF.Net email is sponsored by:
Sybase ASE Linux Express Edition - download now for FREE
LinuxWorld Reader's Choice Award Winner for best database on Linux.
http://ads.osdn.com/?ad_idU88&alloc_id065&op=click
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.sourceforge.net/lists/listinfo/xen-devel