From owner-freebsd-hackers@FreeBSD.ORG Wed Jul 25 10:26:22 2012 Return-Path: Delivered-To: hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 36C3A106566C; Wed, 25 Jul 2012 10:26:22 +0000 (UTC) (envelope-from ryao@gentoo.org) Received: from smtp.gentoo.org (smtp.gentoo.org [140.211.166.183]) by mx1.freebsd.org (Postfix) with ESMTP id 090DB8FC17; Wed, 25 Jul 2012 10:26:22 +0000 (UTC) Received: from [192.168.1.2] (pool-72-89-250-138.nycmny.fios.verizon.net [72.89.250.138]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: ryao) by smtp.gentoo.org (Postfix) with ESMTPSA id CAF471B4678; Wed, 25 Jul 2012 10:26:20 +0000 (UTC) Message-ID: <500FC945.8010602@gentoo.org> Date: Wed, 25 Jul 2012 06:24:05 -0400 From: Richard Yao User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.5) Gecko/20120628 Thunderbird/10.0.5 MIME-Version: 1.0 To: Wojciech Puchar References: <50085193.6030203@gentoo.org> <5009DB2A.7070408@gentoo.org> <500A13A6.7030503@gentoo.org> <500B795B.7000307@gentoo.org> <63653b2570964cb995f7191fabdb52c8@HUBCAS2.cs.stonybrook.edu> In-Reply-To: <63653b2570964cb995f7191fabdb52c8@HUBCAS2.cs.stonybrook.edu> X-Enigmail-Version: 1.3.5 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig7F1E5AD08EEA7A960EB00674" Cc: Richard Yao , "hackers@FreeBSD.org" , "ivoras@freebsd.org" , Adrian Chadd , "current@freebsd.org" Subject: Re: Awful FreeBSD 9 block IO performance in KVM X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 25 Jul 2012 10:26:22 -0000 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig7F1E5AD08EEA7A960EB00674 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable On 07/22/2012 03:19 AM, Wojciech Puchar wrote: >> You are right. It is not capped at that speed: >> >> root@freebsd:/root # dd if=3D/dev/zero of=3D/dev/da1 bs=3D16384 count=3D= 262144 >> >> >> >> 262144+0 records in >> 262144+0 records out >> 4294967296 bytes transferred in 615.840721 secs (6974153 bytes/sec) >> >> > you did test da1 while dmesg are about da0? >=20 > is it OK and da1 is another qemu-kvm vdisk? >=20 > If so, check >=20 > dd if=3D/dev/zero of=3D/dev/da1 bs=3D512 count=3D256k >=20 > and compare speed. >=20 > i bet at something near 250kB/s and i think it is long I/O service=20 > pathlength in qemu-kvm SCSI device simulator. >=20 > Just my bet i don't run FreeBSD on any VM (as opposed to running Window= s=20 > under FreeBSD in VBox) >=20 > check out how much CPU is used on the host side when you do that test. > _______________________________________________ > freebsd-hackers@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-hackers > To unsubscribe, send any mail to "freebsd-hackers-unsubscribe@freebsd.o= rg" The test was on da1, but that does not explain how Linux manages to get over 100MB/s when writing to a file on ext4. I will do some more comprehensive tests as soon as I find time. --------------enig7F1E5AD08EEA7A960EB00674 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQIcBAEBAgAGBQJQD8lIAAoJECDuEZm+6Exk+DsP/jvqXUDEBlglCP79abNDJ3zy F/Au0LCk8ylgQwvNbS5vRJy0lMpfYZKjywNh/8A84b9kfqcshmpFZdwoiOyM/Z5X i3iuQTwwbXIQ91C53fE9wSfK2bmoXBM+zbLPMmaLw1qklk9H8/JGnAVT8UvyS+SW lAVUVO25NDsKoJT6Yh/S1xqdaUGpGIsjBqKxl6S4ZvWuamb7ZHoHUuRithwRWRRF GzfKky1FZ/gTRC5TLXXgaaXN9xpDz0O7mmCYvmNI/2JE9L9LgxP+zq5edpyIJ1ch bOcmjegbJ1i77D+6v+8kPg6HLFw97MUJqGczq1IbEcliWlWBBjlBHe0hwoOi2ARD gD4/v7OKmnOJb2dZEthOI/EF6bwWEE6EWhmT+/XRf3oGrgxf6ZtTmK9hLu95wDbn OTLQyNPHB88yJCLsyHuDKut9Ny7pph3hDBQHACPmy9MmQHvW8/RIIORBIfGz+T5/ ddcnLno4HXkIRtkewmiJUApkjUq+fSdchEYu2DzrgKvNvWkAP/vSBNYq6IWnD3Nf P8NPoADV/VxB2rQwvrTqJboRbH7bXik2fqbAMerUHmek0BcszS0P6o0Xr2YEEK+R uD3ov/Yb9332HD0aBsMiAWrn08eiFiz9diSf7Jgwlm/2AvXFW5GYmBznuSENP6oK mku1FyTDw336awa/sWea =V+nb -----END PGP SIGNATURE----- --------------enig7F1E5AD08EEA7A960EB00674--