| Well, I just go throught the source of irqbalance, it shows that it balances the irq through updating /proc/irq/$irq/smp_affinity.  That, in my understanding, set irq affinity is almost
 equal to irq migration.
 
 I later find the NIC  interrupt is not modified in dom0, so it is safe to set its  affinity,
 but  interrupt of xen event use handle_level_irq, set its affinity will subject to irq
 lost.
 
 Am I right?
 
 > Date: Tue, 28 Sep 2010 10:07:28 -0700
 > From: jeremy@xxxxxxxx
 > To: tinnycloud@xxxxxxxxxxx
 > CC: xen-devel@xxxxxxxxxxxxxxxxxxx; keir.fraser@xxxxxxxxxxxxx
 > Subject: Re: [Xen-devel] Re: VM hung after running sometime
 >
 > On 09/28/2010 04:23 AM, MaoXiaoyun wrote:
 > >
 > > Is it safe to set irq affinity(including NIC, domain event, etc) manually?
 > > Will it cause irq lost?
 >
 > There's only a very small chance of a lost interrupt, especially if the
 > device is mostly idle at the time. The event can only be lost if:
 >
 > 1. it is handling a device interrupt
 > 2. you migrate it to another cpu
 > 3. another interrupt comes in before the first one has finished
 > processing
 >
 > J
 >
 
 |