From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=48867 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PhlNc-0004nT-1M for qemu-devel@nongnu.org; Tue, 25 Jan 2011 11:04:37 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PhlNX-0006q2-IW for qemu-devel@nongnu.org; Tue, 25 Jan 2011 11:04:24 -0500 Received: from mx1.redhat.com ([209.132.183.28]:56023) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PhlNX-0006pH-5C for qemu-devel@nongnu.org; Tue, 25 Jan 2011 11:04:23 -0500 Message-ID: <4D3EF483.5090308@redhat.com> Date: Tue, 25 Jan 2011 17:04:19 +0100 From: Jes Sorensen MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: [Qemu-devel] QEMU/KVM Call notes for Jan 25, 2011 List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: QEMU Developers , KVM General Cc: Chris Wright Hello, Please find attached my notes from the weekly QEMU/KVM call January 25, 2011. My apologies if I got something wrong. Jes - QEMU 0.14/0.15 releases - Feb 1st 2011 branch to stable tree for 0.14. Anthony would like to do a formal release quickly, so hopefully within 1-2 weeks after snapshot (Feb 15, 2011). - We should plan a formal release schedule for 0.15 http://wiki.qemu.org/Planning/0.15-example - coroutines - Proposal from Stefan Hajnoczi http://www.mail-archive.com/qemu-devel@nongnu.org/msg52522.html - First example is to try and calls to synchronous system calls in QCOW2 codebase. - Suggest every image format in block layer have it's own coroutine layer. - Long term, can/should we apply this to entire block layer? Q: Can we go to real threads in the block layer? A: coroutines are light weight, and we have more control, but it is an option. Going to threads would require a serious amount of work making the full QEMU stack thread safe. Doesn't solve the parallelism problem, so not the final long term solution to the scalability problem. Q: Should we do coroutines in the block layer rather than the image formats? This would provide aio support for formats that do not currently implement aio calls. A: Avi suggests mixed approach, to benefit from not having explicit synchronization points in high performance formats. Follow-on longer discussion about implementation details, which is to be followed up in email. - glib integration - Proposal from Anthony http://www.mail-archive.com/qemu-devel@nongnu.org/msg52798.html - Provides portable interfaces to threading, data structures, and utility functions. - Idea would be to get rid of a lot of duplicated code which we would get from glib instead. - Also consider gio and gobject. - gobject could be a replacement for qdev - gobject could help make vnc server become standalone - Not suggesting to convert everything to glib types (gint, guint, etc). Clarification of which types are recommended will be needed in CODING_STYLE Q: Which would be the first subsystem to convert A: Convert QEMU threads to gthreads - Comment, doing a conversion of QMP would be good, but Luiz will not have time to look at this for maybe 2 months. - Suggestion from Paolo Bonzini to make a standalone library for JSON, rather than relying on the glib implementation - Google Summer of Code 2011 - please post suggestions to the list, and we should revisit this item next week.