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From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] rps: send IPIs ASAP
Date: Mon, 19 Apr 2010 22:39:36 -0700 (PDT)
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From: Tom Herbert <therbert@google.com>
Date: Mon, 19 Apr 2010 22:15:58 -0700

> Did you test this to see what the impact is in this regard?

Changli it would help immensely if you posted performance
test results along with your changes.

I can see quite obviously that this change will completely undo the
intentional batching of IPIs done by RPS.  IPIs are expensive and we
should batch things as much as possible here.