From mboxrd@z Thu Jan 1 00:00:00 1970 From: Samuel Thibault Subject: Re: [RFC][PATCH] Add HPET emulation to qemu (v2) Date: Sat, 2 Aug 2008 12:38:12 +0100 Message-ID: <20080802113812.GD4535@implementation> References: <1217675114-17670-1-git-send-email-eak@us.ibm.com> Reply-To: qemu-devel@nongnu.org Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Cc: Beth Kon , Alexander Graf , kvm@vger.kernel.org To: qemu-devel@nongnu.org Return-path: Content-Disposition: inline In-Reply-To: <1217675114-17670-1-git-send-email-eak@us.ibm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org Errors-To: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org List-Id: kvm.vger.kernel.org Beth Kon, le Sat 02 Aug 2008 06:05:14 -0500, a écrit : > I was trying to reproduce the wakeup every 10ms that > Samuel Thibault mentioned, thinking the HPET would improve it. > But for an idle guest in both cases (with and without HPET), the > number of wakeups per second was relatively low (28). I was referring to vl.c's timeout = 10; which makes the select call use a timeout of 10ms. That said, "/* If all cpus are halted then wait until the next IRQ */", so maybe that's why you get slower wakeups per second. I'm still surprised because of the call to qemu_mod_timer in pit_irq_timer_update which should setup at least a 100Hz timer with linux guests (when they don't have HPET available). Samuel