From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 87160C369AB for ; Mon, 21 Apr 2025 13:39:52 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1u6rMO-00047O-8U; Mon, 21 Apr 2025 09:38:56 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1u6rMM-00047A-PK for qemu-devel@nongnu.org; Mon, 21 Apr 2025 09:38:54 -0400 Received: from mx.treblig.org ([2a00:1098:5b::1]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1u6rMK-0007OW-F0 for qemu-devel@nongnu.org; Mon, 21 Apr 2025 09:38:54 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=treblig.org ; s=bytemarkmx; h=Content-Type:MIME-Version:Message-ID:Subject:From:Date:From :Subject; bh=bDW0R29TftOhMM4odMLyTAu+oTVdHSq9+IqBavuwSCU=; b=qsB4QlbRm5fH0g+c M73FHeFY9U29f0laWsF0O/M5i2LWKiX6vKQxVAUwKFUlVh2LrL96WFSQC49+/jpdHVnxbZWdjXJrU vgJeQIQSnNxPUZ4v2fVNfx8OSj9FTXz0UGsKdqHTPryBNCV44IYvINhKDY+xtiEloxLvpAeHmBucf fAWE8B57G3jun1IjbJmg1o78w/EAeBZhng/K5O8q8RhvOTbBpQJ5Ef+bEI+ONE7HilxUlPKqi7Cn4 rvMQQ8rD5/d3nCi8Z3wlwcRytx0dTweoJHW3n/4xsnlKPgcI777bfA4HMkDYQxUr/HVysotySYrEy i4ROycVZwErnayXCfw==; Received: from dg by mx.treblig.org with local (Exim 4.96) (envelope-from ) id 1u6rMG-00Cpp7-0q; Mon, 21 Apr 2025 13:38:48 +0000 Date: Mon, 21 Apr 2025 13:38:48 +0000 From: "Dr. David Alan Gilbert" To: steven.sistare@oracle.com Cc: qemu-devel@nongnu.org Subject: Trying cpr Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline X-Chocolate: 70 percent or better cocoa solids preferably X-Operating-System: Linux/6.1.0-21-amd64 (x86_64) X-Uptime: 13:27:16 up 348 days, 41 min, 1 user, load average: 0.00, 0.00, 0.00 User-Agent: Mutt/2.2.12 (2023-09-09) Received-SPF: pass client-ip=2a00:1098:5b::1; envelope-from=dg@treblig.org; helo=mx.treblig.org X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Hi Steve, I've just had a go with cpr-transfer, it's quite interesting. I was just trying it on my (AMD) desktop. * I was running with qemu displaying graphics, and after migration the source display got updated every time I moved my mouse into the source window; the VM was still stopped, but I guess that means the source GUI is still parsing the guest VRAM and displaying it. I'm not sure if there's any other interactions - e.g. is there any situation where the source GUI will try and write into the shared guest ram? * Given that you pass fd's over the CPR socket, had you considered passing main migration fd's over it as well, that way you'd only need one incoming. * The guest noticed the time skew: timekeeping watchdog on CPU1: Marking clocksource 'tsc' as unstable because the skew is too large: 'kvm-clock' wd_nsec: 556248511 wd_new: 4a93129e69 wd_alst: 4a71eaf0aa mask: (all f's) 'tsc' cs_nsec: 514023131 cs_now: 1047f1d8489 cs_last: 10414538c1 mask: (all f's) Clocksource 'tsc' skewed -42225380 ns (-42 ms) over watchdog 'kvm-clock' interval of 556248511 ns (556 ms) 'kvm-clock' (not 'tsc') is current clocksource (That was hand copied, probably with some typos - who knew the GUI doesn't let you copy/paste from serial0...) The source commandline was: ./try/qemu-system-x86_64 -object memory-backend-file,id=ram0,size=4G,mem-path=/dev/shm/qemuram0,share=on -m 4G -machine memory-backend=ram0,aux-ram-share=on -cpu host --enable-kvm -smp 16 -drive if=virtio,file=/discs/more/images/debian-13-nocloud-amd64-daily.qcow2 -qmp stdio The dest commandline was: ./try/qemu-system-x86_64 -object memory-backend-file,id=ram0,size=4G,mem-path=/dev/shm/qemuram0,share=on -m 4G -machine memory-backend=ram0,aux-ram-share=on -cpu host --enable-kvm -smp 16 -drive if=virtio,file=/discs/more/images/debian-13-nocloud-amd64-daily.qcow2 -incoming tcp:0:44444 -incoming '{"channel-type": "cpr", "addr": { "transport": "socket", "type": "unix", "path": "cpr.sock"}}' Dave -- -----Open up your eyes, open up your mind, open up your code ------- / Dr. David Alan Gilbert | Running GNU/Linux | Happy \ \ dave @ treblig.org | | In Hex / \ _________________________|_____ http://www.treblig.org |_______/