From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57628) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZEzN6-0002zW-GW for qemu-devel@nongnu.org; Tue, 14 Jul 2015 08:31:41 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZEzN2-0006Ja-5F for qemu-devel@nongnu.org; Tue, 14 Jul 2015 08:31:40 -0400 Date: Tue, 14 Jul 2015 13:31:31 +0100 From: Stefan Hajnoczi Message-ID: <20150714123131.GM17927@stefanha-thinkpad.redhat.com> References: <1436413678-7114-1-git-send-email-famz@redhat.com> <1436413678-7114-2-git-send-email-famz@redhat.com> <20150709125455.GA11166@stefanha-thinkpad.redhat.com> <1233193551.9344767.1436499768115.JavaMail.zimbra@oxygem.tv> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="rf72Gf+bfLC8kxKs" Content-Disposition: inline In-Reply-To: <1233193551.9344767.1436499768115.JavaMail.zimbra@oxygem.tv> Subject: Re: [Qemu-devel] [Qemu-block] [PATCH 1/3] blockjob: Introduce block_job_relax_cpu List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alexandre DERUMIER Cc: Kevin Wolf , Fam Zheng , qemu-devel , qemu-block@nongnu.org --rf72Gf+bfLC8kxKs Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Jul 10, 2015 at 05:42:48AM +0200, Alexandre DERUMIER wrote: > >>By the way, why did you choose 10 milliseconds? That is quite long. > >> > >>If this function is called once per 10 ms disk I/O operations then we > >>lose 50% utilization. 1 ms or less would be reasonable. >=20 > From my tests, 1ms is not enough, It still hanging in guest or qmp querie= s. > 10ms give me optimal balance between bitmap scan speed and guest responsi= veness. Then I don't fully understand the bug. Fam: can you explain why 1ms isn't enough? --rf72Gf+bfLC8kxKs Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAEBAgAGBQJVpQEjAAoJEJykq7OBq3PIob0H/j5BDBFFFzFghC2ebIrRjELL 7wmNUbTpIBlbWwdsdeGrJLrBhJfP8I2iZZeJWbIF/5nep833HAVWb8XSa84SHz3+ tdaYCosLOy3v0jINJZDbs1yUsr8a1AJEQ8TXTBHPGVCUNPzoC+xR65wHFhQFDyuz /lxqq4SJA8lteYZu3Ug2fPBQKQNuvM/u9/oniXaAG+N4zn2TZdJYvo/FQop3DVB3 nYMw7Z7p8yAHO8dVZNxtuKf2zyJAsWIFHV8PWCa8FpfAldtBjPNFw7pqW1awTITh gp73pGRPP5XNnPfPcECvLBRpsyJKGFmK6t3yOYRtiZFcC1dqLMuYYRxi9X6+VKI= =zKZs -----END PGP SIGNATURE----- --rf72Gf+bfLC8kxKs--