Re: irq load balancing

2007-09-13 Thread Chris Snook
Venkat Subbiah wrote: Since most network devices have a single status register for both receiver and transmit (and errors and the like), which needs a lock to protect access, you will likely end up with serious thrashing of moving the lock between cpus. Any ways to measure the trashing of locks?

RE: irq load balancing

2007-09-13 Thread Venkat Subbiah
Venkat -Original Message- From: Lennart Sorensen [mailto:[EMAIL PROTECTED] Sent: Thursday, September 13, 2007 1:45 PM To: Venkat Subbiah Cc: Chris Snook; linux-kernel@vger.kernel.org Subject: Re: irq load balancing On Thu, Sep 13, 2007 at 01:31:39PM -0700, Venkat Subbiah wrote: > Doing it i

Re: irq load balancing

2007-09-13 Thread Lennart Sorensen
On Thu, Sep 13, 2007 at 01:31:39PM -0700, Venkat Subbiah wrote: > Doing it in a round-robin fashion will be disastrous for performance. > Your cache miss rate will go through the roof and you'll hit the slow > paths in the network stack most of the time. > > Most of the work in my system is spent i

RE: irq load balancing

2007-09-13 Thread Venkat Subbiah
September 12, 2007 2:45 PM To: Venkat Subbiah Cc: linux-kernel@vger.kernel.org Subject: Re: irq load balancing Venkat Subbiah wrote: > Most of the load in my system is triggered by a single ethernet IRQ. > Essentially the IRQ schedules a tasklet and most of the work is done in the > taskel

Re: irq load balancing

2007-09-12 Thread Chris Snook
Venkat Subbiah wrote: Most of the load in my system is triggered by a single ethernet IRQ. Essentially the IRQ schedules a tasklet and most of the work is done in the taskelet which is scheduled in the IRQ. From what I read looks like the tasklet would be executed on the same CPU on which it was

Re: irq load balancing

2007-09-12 Thread Arjan van de Ven
On Tue, 11 Sep 2007 16:18:15 -0700 "Venkat Subbiah" <[EMAIL PROTECTED]> wrote: > Most of the load in my system is triggered by a single ethernet IRQ. > Essentially the IRQ schedules a tasklet and most of the work is done > in the taskelet which is scheduled in the IRQ. From what I read looks > lik

Re: irq load balancing

2007-09-12 Thread kalash nainwal
On 9/12/07, Venkat Subbiah <[EMAIL PROTECTED]> wrote: > Most of the load in my system is triggered by a single ethernet IRQ. > Essentially the IRQ schedules a tasklet and most of the work is done in the > taskelet which is scheduled in the IRQ. From what I read looks like the > tasklet would be

Re: irq load balancing

2007-09-12 Thread Stephen Hemminger
On Tue, 11 Sep 2007 16:18:15 -0700 "Venkat Subbiah" <[EMAIL PROTECTED]> wrote: > Most of the load in my system is triggered by a single ethernet IRQ. > Essentially the IRQ schedules a tasklet and most of the work is done in the > taskelet which is scheduled in the IRQ. From what I read looks lik