From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Alan D. Brunelle" Date: Thu, 05 Feb 2009 11:42:00 +0000 Subject: Re: blktrace2: Fully working variant... Needs testing... :-) Message-Id: <498AD088.4070000@hp.com> List-Id: References: <498A0D14.3080000@hp.com> In-Reply-To: <498A0D14.3080000@hp.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-btrace@vger.kernel.org Alan D. Brunelle wrote: > I'm seeing some positive results on my 16-way amd64 box (w/ 48 FC disks > & 48 CCISS disks) - less intrusive blktrace()ing, resulting in more > benchmark through put for example. > > It seems to be pretty valgrind clean (only issue I've seen is in > inet_ntoa: man page says it uses static storage, but valgrind claims it > uses malloc - nothing for us to be concerned with). > > Anyways, I'm putting this out there whilst I do some more testing to > verify things. > Some good news: doing my previously reported testing on the balanced configuration completed successfully. (mkfs on large numbers of CCISS disks, tracing to a large number of FC disks) What is more, it appears to be a little better in terms of fewer drops & fewer drop cases - results below are in percent drops: blktrace: -b 4 8 16 32 64 128 256 512 1024 2048 4096 -n |----- ----- ----- ----- ----- ----- ----- ----- ----- ----- ----- 4| 4.4 0.0 0.0 0.0 8| 1.5 0.0 16| 0.1 0.0 32| 0.8 0.0 64| 1.1 128| 0.8 256| 2.6 512| 2.3 1024| 0.5 2048| 0.1 4096| 0.0 blktrace2: -b 4 8 16 32 64 128 256 512 1024 2048 4096 -n |----- ----- ----- ----- ----- ----- ----- ----- ----- ----- ----- 4| 0.2 0.0 0.0 0.0 8| 0.1 0.0 16| 0.0 0.0 32| 0.0 0.0 64| 0.1 128| 0.1 256| 0.1 512| 0.2 1024| 0.0 2048| 0.0 4096| 0.0 The goal now will be to try and see if I can wiggle out the remaining 0.1 or 0.2% drops... Alan