[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: [Xen-devel] Interrupt Coalescence


  • To: "Hevard Bjerke" <havarbj@xxxxxxxxxxx>
  • From: "Ian Pratt" <m+Ian.Pratt@xxxxxxxxxxxx>
  • Date: Sat, 13 Nov 2004 21:24:10 -0000
  • Cc: <xen-devel@xxxxxxxxxxxxxxxxxxxxx>
  • Delivery-date: Sat, 13 Nov 2004 21:51:52 +0000
  • List-id: List for Xen developers <xen-devel.lists.sourceforge.net>
  • Thread-index: AcTIpww3CZhtrkNlTvO6nKXn2iRhZgBHv+/w
  • Thread-topic: [Xen-devel] Interrupt Coalescence

> > What happenes if you boot with 'igrnorebiostables' on the 
> Xen command line (this forces uniprocessor)?  This will use 
> the legacy PIC rather than the IOAPIC.
> >  
> I've already found that 'ignorebiostables' solves the IOAPIC 
> problem, giving equal performance in native and dom0.
> 
> Whether with or without 'ignorebiostables', disabling IC 
> leads to dramatically reduced bandwidth in dom0 but not in native.

I'm rather more interested in getting the IOAPIC working on your
platform than figuring out what's going on with the legacy PIC. Can you
say a bit about the CPU and chipset you're using? 

Since it looks like there's a nasty interrupt problem on your system,
it's perhaps not surprising that disabling interrupt coallescing causes
problems. My guess is that you end up doing some nasty spinning iwithin
Xen. 

Could you get a serial line on the system to enable you to readout the
Xen s/w performance counters? (hit 'p' to print, 'P' to reset) 

Ian


-------------------------------------------------------
This SF.Net email is sponsored by: InterSystems CACHE
FREE OODBMS DOWNLOAD - A multidimensional database that combines
robust object and relational technologies, making it a perfect match
for Java, C++,COM, XML, ODBC and JDBC. www.intersystems.com/match8
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.sourceforge.net/lists/listinfo/xen-devel


 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.