From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38853) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XsxFT-0004o9-Jd for qemu-devel@nongnu.org; Mon, 24 Nov 2014 12:16:31 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XsxFP-0007Vg-3X for qemu-devel@nongnu.org; Mon, 24 Nov 2014 12:16:27 -0500 Received: from mx1.redhat.com ([209.132.183.28]:60940) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XsxFO-0007Ux-Rk for qemu-devel@nongnu.org; Mon, 24 Nov 2014 12:16:23 -0500 Message-ID: <547367E3.1040304@redhat.com> Date: Mon, 24 Nov 2014 10:16:19 -0700 From: Eric Blake MIME-Version: 1.0 References: <1415272128-8273-1-git-send-email-liang.z.li@intel.com> <1415272128-8273-3-git-send-email-liang.z.li@intel.com> <545B703E.7030907@redhat.com> In-Reply-To: Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="fvsOecQxU7jA7Rad3kGRMeMlTAh5FMeWf" Subject: Re: [Qemu-devel] [v2 2/2] migration: Implement multiple compression threads List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Li, Liang Z" , "qemu-devel@nongnu.org" Cc: "Zhang, Yang Z" , "armbru@redhat.com" , "lcapitulino@redhat.com" This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --fvsOecQxU7jA7Rad3kGRMeMlTAh5FMeWf Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On 11/23/2014 07:25 PM, Li, Liang Z wrote: >>> # @auto-converge: If enabled, QEMU will automatically throttle down = the guest >>> # to speed up convergence of RAM migration. (since 1.6) >>> # >>> # Since: 1.2 >>> ## >>> { 'enum': 'MigrationCapability', >>> - 'data': ['xbzrle', 'rdma-pin-all', 'auto-converge', 'zero-blocks']= =20 >>> } >>> + 'data': ['xbzrle', 'rdma-pin-all', 'auto-converge', 'zero-blocks',= =20 >>> + 'compress'] } >>> =20 >=20 >> I'll repeat what I said on v1 (but this time, with some links to back = it up :) >=20 >> We really need to avoid a proliferation of new commands, two per tunab= le does not scale well. I think now is the time to implement my earlier = suggestion at making MigrationCapability become THE resource for > tunabl= es: [please configure your mailer to wrap long lines] >=20 >> https://lists.gnu.org/archive/html/qemu-devel/2014-03/msg02274.html >=20 > Hi, Eric >=20 > I have read your proposal, and I just want to verify if I got it= exactly. Take the 'compresss-level' parameter for example, according t= o you suggestion, should I implement a command 'set-migrate-capability co= mpress-level 1', or 'set-migrate-parameter compress-level 1' ? if it's= the former, how to keep the HMP back compatibility, as you know, the cur= rent HMP framework will check the parameter type, the 'int' will be proce= ssed differently from 'bool', ; if it's the latter, it seems like a ' q= uery-migrate-paramer ' command should be provided to keep consistency, no= t query-migrate-capability. HMP back-compat is NOT a problem we need to worry about; it's okay to break the semantics if something else is easier to represent; it is only QMP where we have to remain backwards compatible. We already have set-migrate-capability, so that seems like the command to extend, instead of adding a new one. On the other hand, if it is easier for you to add a new HMP command that maps correctly to the underlying QMP command, then that is fine, too. The point of my proposal is that the QMP command can use a union to provide the correct typing as needed, without worrying about what HMP has to do to match that. --=20 Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org --fvsOecQxU7jA7Rad3kGRMeMlTAh5FMeWf Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: Public key at http://people.redhat.com/eblake/eblake.gpg iQEcBAEBCAAGBQJUc2fjAAoJEKeha0olJ0Nqjl4IAIcL0hvsQCztSW0cUuFbCCQ/ b9k5LbR45V7Y/8pYiEZ1wwYWJzMgNPuy9r3UEja80Hy6MrecnZAFMUkc6yCqugYN BD4D2PlIH8vu3O91Yxqv3EGIg1smisoJRPbiwaHeTBtBn+XHwNfqpMFZs/lWCQKs YuBN0baRwasgnk5JOihYNunc+Cqi+cUO8D2uhZDldFtm99NUsVS6UbHxxx12dQ7I TBXzUCILMLxUc3kErZ9tDw07BCipju0YzFaKiCXrHMmQjMdZmYLZ9zwfyUWNkuJ1 9XkwWOn2Z9tdMEeThCOUj7o1l+wMC0qgYwxfhonhs/KVVRr79C7cIb1Id1gEtcY= =iQEE -----END PGP SIGNATURE----- --fvsOecQxU7jA7Rad3kGRMeMlTAh5FMeWf--