From mboxrd@z Thu Jan 1 00:00:00 1970 From: cwillu Subject: Re: very poor read / write performance compared to other FS's? Date: Wed, 11 May 2011 16:41:10 -0600 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Cc: linux-btrfs@vger.kernel.org To: Marek Fstump Return-path: In-Reply-To: List-ID: On Wed, May 11, 2011 at 4:33 PM, Marek Fstump w= rote: > Hi > > I am very interested in using BTRFS for my solution but in basic test= s > it seems to be very poor on read and write performance. =C2=A0I am > surprised by this so suspect that maybe I am doing something > incorrectly or that there are updates I should be using, but I am not > sure how I update BTRFS on SLES11 > > Summary: > RESULTS on link below > SLES11 SP1 > Compared Sequential read/write performance against XFS and OCFS2 > Backend storage =E2=80=93 FusionIO SLC SSD =3D circa 750MBsec > > Tests =C2=A0set as follows: > Filesystem contains 30 x 4GB files (made of random data) > Read tests will read from 1 to 30 files concurrently > Write tests will write 1 to 30 concurrent NEW files (simple 000=E2=80= =99s) > dd -direct flag used on writes > > All defaults used for mounting etc. > > Results shown in attachment. > > BTRFS looks an excellent FS and perfect for my application and I am > hoping that there are some factors that I am missing > and would appreciate any advice / help > > Graph is here (Thank you =E2=80=98cwillu=E2=80=99) > > http://cwillu.com/files/btrfs/read-write_perf.pdf A couple questions: Which kernel version? How big is the partition the testing is done on? How does btrfs compare if you drop the -direct flag, and instead sync + drop_caches before, and time until sync completes after dd (for all of them, not just btrfs)? There are a couple btrfs mount options that will improve performance in this particular case, but this benchmark may not reflect your actual needs. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" = in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html