From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1HMlRd-0005yA-92 for qemu-devel@nongnu.org; Thu, 01 Mar 2007 08:35:41 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1HMlRa-0005tv-Pn for qemu-devel@nongnu.org; Thu, 01 Mar 2007 08:35:40 -0500 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1HMlRa-0005tk-Md for qemu-devel@nongnu.org; Thu, 01 Mar 2007 08:35:38 -0500 Received: from web32009.mail.mud.yahoo.com ([68.142.207.106]) by monty-python.gnu.org with smtp (Exim 4.52) id 1HMlRZ-0001fM-H9 for qemu-devel@nongnu.org; Thu, 01 Mar 2007 08:35:37 -0500 From: Uri Lublin MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Message-ID: <399896.28101.qm@web32009.mail.mud.yahoo.com> Subject: [Qemu-devel] QEMU temporarily hangs Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Date: Thu, 01 Mar 2007 13:35:41 -0000 To: qemu-devel@nongnu.org Hello, Second attempt (with minor modifications), as the first one did not arrive. I would like to share with you a QEMU problem I've encountered, and hope to get pointers where to look for it. I am running CVS QEMU, x86_64-softmmu, with vmdk image and redirected monitor (unix socket). If the guest is busy and I rapidly send a LOT of commands to QEMU monitor, then eventually QEMU temporarily hangs (vnc and monitor are not responsive) At that state: - QEMU process's cpu usage is around 100% - strace shows ONLY clock_gettime(CLOCK_MONOTONIC, {time changing}) = 0 - pstack shows: #0 0x0000003603e0459b in clock_gettime () from /lib64/librt.so.1 #1 0x0000000000405c9d in get_clock () #2 0x0000000000405d65 in cpu_get_clock () #3 0x000000000044f660 in pit_get_count () #4 0x000000000044f805 in pit_latch_count () #5 0x0000000002450ec8 in code_gen_buffer () #6 0xbe26f6118053c79f in ?? () #7 0x000000000047df6e in cpu_x86_exec () #8 0x000000000040c11a in main_loop () #9 0x000000000040da69 in main () After a while (few or more minutes), it comes back to life. I can shorten my waiting time by sending a SIGUSR2 signal to QEMU (SIGIO and SIGALRM work too). Why doesn't host_alarm_handler() get called/bring QEMU back to life ? Any comment would be appreciated, Thanks, Uri. ____________________________________________________________________________________ Finding fabulous fares is fun. Let Yahoo! FareChase search your favorite travel sites to find flight and hotel bargains. http://farechase.yahoo.com/promo-generic-14795097