On 04/05/2013 07:32 PM, Bill Maidment wrote:
> After switching back to the older kernel, I can confirm that the swap
> usage has returned to normal, even during the backup time 6am-8am. (See
> attached graph)
>
> I'm wondering if this has anything to do with NUMA, which sometimes
> prefers to use swap rather than memory that is slightly slower than the
> currently used memory.
>
> I am using a single Phenom II 955 processor (quad core) on an ASUS
> M4N68T motherboard and SL6.4 upgraded from 6.3

Switching back fixed it for me too.  Max swap usage reduced from 100% to 
25%, all dumps completed on time.  I suppose NUMA could be a factor, 
this is a Xeon L5520 system.  I haven't seen this large swap usage on my 
other older hardware, although I only have the one machine writing 
backups to local disk, remote machines send the backup via the network 
to this host.

I've filed https://bugzilla.redhat.com/show_bug.cgi?id=949166


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