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Date: Tue, 14 Jun 2011 17:32:47 -0500
From: Clay Andreasen <cda@cray.com>
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Subject: [Qemu-devel] High speed polling
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To: qemu-devel@nongnu.org

I have a network device simulation that I am connecting to multiple
instances of Qemu (nodes) via a shared memory queue.  It works pretty 
well as
long as all of the nodes are initiating communication but when one node is
passive, it must poll to get packets.  So far the fastest I have been 
able to
get it to poll is about every 2M emulated clocks.
This is with CONFIG_HIGH_RES_TIMERS and CONFIG_NO_HZ on the host.
I also set MIN_TIMER_REARM_NS in qemu-timer.c to 100000.
Is there some way to increase the polling rate by about an order of 
magnitude?