Re: One random read streaming is fast (~1200MB/s), but two or more are slower (~750MB/s)?

2013-05-02 Thread Matt Pursley
one 1048576 bytes (10 GB) copied, 64.5931 s, 162 MB/s kura1 btrfs_test # sysctl vm.drop_caches=1 ; for j in {1..1} ; do dd of=/dev/null if=/tmp/btrfs_test/testfile_bs1m_size10GB_${j} bs=1M & done 1048576 bytes (10 GB) copied, 64.6299 s, 162 MB/s ___ ====== On Fri, A

Re: One random read streaming is fast (~1200MB/s), but two or more are slower (~750MB/s)?

2013-04-26 Thread Matt Pursley
e the same results with multiple drives in your raid... Thanks, Matt On Thu, Apr 25, 2013 at 2:10 PM, Josef Bacik wrote: > On Thu, Apr 25, 2013 at 03:01:18PM -0600, Matt Pursley wrote: >> Ok, awesome, let me know how it goes.. I don't have the raid >> formatted to btr

Re: One random read streaming is fast (~1200MB/s), but two or more are slower (~750MB/s)?

2013-04-25 Thread Matt Pursley
Ok, awesome, let me know how it goes.. I don't have the raid formatted to btrfs right now, but I could probably do that in about 30 minutes or so. Thanks Josef, Matt On Thu, Apr 25, 2013 at 1:39 PM, Josef Bacik wrote: > On Thu, Apr 25, 2013 at 01:52:44PM -0600, Matt Pursley wrote

Re: One random read streaming is fast (~1200MB/s), but two or more are slower (~750MB/s)?

2013-04-25 Thread Matt Pursley
Hey Josef, Were you able to look into this any further? It's still pretty reproducible on my machine... Thanks, Matt On Thu, Apr 18, 2013 at 2:58 PM, Josef Bacik wrote: > This is strange, and I can't see any reason why this would happen. I'll try > and > reproduce next week when I'm bac

Re: One random read streaming is fast (~1200MB/s), but two or more are slower (~750MB/s)?

2013-04-17 Thread Matt Pursley
( sysctl vm.drop_caches=1; dd of=/dev/null if=/var/data/persist/testfile2 bs=640k ) _ On Wed, Apr 17, 2013 at 10:30 AM, Matt Pursley wrote: > On Tue, Apr 16, 2013 at 11:55 PM, Sander wrote: >> Matt Pursley wrote (ao): >>> I have an LSI HBA card (LSI SAS 9207-

Re: One random read streaming is fast (~1200MB/s), but two or more are slower (~750MB/s)?

2013-04-17 Thread Matt Pursley
On Tue, Apr 16, 2013 at 11:55 PM, Sander wrote: > Matt Pursley wrote (ao): >> I have an LSI HBA card (LSI SAS 9207-8i) with 12 7200rpm SAS drives >> attached. When it's formated with mdraid6+ext4 I get about 1200MB/s >> for multiple streaming random reads with iozone.

One random read streaming is fast (~1200MB/s), but two or more are slower (~750MB/s)?

2013-04-16 Thread Matt Pursley
Hi All, I have an LSI HBA card (LSI SAS 9207-8i) with 12 7200rpm SAS drives attached. When it's formated with mdraid6+ext4 I get about 1200MB/s for multiple streaming random reads with iozone. With btrfs in 3.9.0-rc4 I can also get about 1200MB/s, but only with one stream at a time. As soon as