From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laurent Riffard Subject: Re: 2.6.16-rc6-mm2: slow writes on reiser4. Date: Wed, 29 Mar 2006 08:16:55 +0200 Message-ID: <442A2657.1090408@free.fr> References: <44206D3C.7050504@free.fr> <4420FFA2.1090908@namesys.com> <44219CC2.3060405@free.fr> <44219FA8.2050606@namesys.com> <44299A35.50800@free.fr> <20060328224945.0A258134@philou.gramoulle.local> Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Return-path: list-help: list-unsubscribe: list-post: Errors-To: flx@namesys.com In-Reply-To: <20060328224945.0A258134@philou.gramoulle.local> List-Id: Content-Type: text/plain; charset="iso-8859-1" To: =?ISO-8859-15?Q?Philippe_Gramoull=E9?= , reiserfs-list@namesys.com Le 29.03.2006 00:49, Philippe Gramoull=E9 a =E9crit : > Hello Laurent, >=20 > On Tue, 28 Mar 2006 22:19:01 +0200 > Laurent Riffard wrote: >=20 > | These FS are quite similars. Now guess what ? I filled these FS with > | dd. > |=20 > | Original FS > | =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > | # sync > | # time dd if=3D/dev/zero of=3Dtoto bs=3D1M count=3D150 > | 103+0 enregistrements lus. > | 102+0 enregistrements =E9crits. > | Command exited with non-zero status 1 >=20 > Well, at least on my system , such a command exits with a 0 status Oops ! I trimmed a line when I cut'n'paste. dd exits with the message "Aucun espace disponible sur le p=E9riph=E9rique" which means "No space left on device". > Also, not a single of your posts in this thread has this error except thi= s one > and the one below Yes I somewhat changed my test. On the previous test, I dd'd 100M to the FS. As the original FS and its copy have different free space, writing 100M on each FS results in 3M free versus 30M free. I did this test and I it takes about 2'20" versus 15". But I feared that one objects "It's because you have less free space on the first FS". So I found more conclusive to write 150M and thus to fill up the 2 FS. > | 0.00user 2.94system 3:32.18elapsed 1%CPU (0avgtext+0avgdata > | 0maxresident)k > | # time sync > | 0inputs+0outputs (0major+279minor)pagefaults 0swaps > | 0.00user 0.01system 0:00.18elapsed 6%CPU (0avgtext+0avgdata > | 0maxresident)k > | 0inputs+0outputs (0major+191minor)pagefaults 0swaps > |=20 > | Copy FS > | =3D=3D=3D=3D=3D=3D=3D > | # sync > | # time dd if=3D/dev/zero of=3Dtoto bs=3D1M count=3D150 > | dd: =E9criture de `toto': Aucun espace disponible sur le p=E9riph=E9r= ique > | 132+0 enregistrements lus. > | 131+0 enregistrements =E9crits. > | Command exited with non-zero status 1 >=20 > Here, i can understand the "exited with non-zero status 1" as > "Aucun espace disponible sur le p=E9riph=E9rique" is french for=20 > "No space left on device" yes, see above. > | 0.00user 4.08system 0:15.95elapsed 25%CPU (0avgtext+0avgdata > | 0maxresident)k > | 0inputs+0outputs (1major+279minor)pagefaults 0swaps > | # time sync > | 0.00user 0.00system 0:00.17elapsed 0%CPU (0avgtext+0avgdata > | 0maxresident)k > | 0inputs+0outputs (0major+190minor)pagefaults 0swaps > | disk$ > |=20 > | See ? 3'30" versus 16". >=20 > Are the 16" due to the fact that the above command exited earlier than it= should have ? No, (see above), both FS were filled up to 0M free space. > Thanks, >=20 > Philippe >=20 Thanks for your comments. I hope this made it clear. To be fair, you can see there is some differences between the 2 FS : - the copy is larger than the original one : 995998 bytes vs 1003520, which is 0.75% larger. - the original FS resides on an extended partition (/dev/hda8) while the copy is on a logical volume (/dev/vglinux1/test). This LV is hosted on /dev/hda4. I hope these differences do not have a high impact on the results. I'll try to dd of=3D/dev/hda8 if=3D/dev/vglinux1/test, and see if it makes some differences when I dd a 100M file on the FS. ~~ laurent