From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Date: Wed, 22 Apr 2015 22:51:36 +0000 Subject: Re: Capturing idle time with blktrace Message-Id: <553825F8.5070903@kernel.dk> List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-btrace@vger.kernel.org On 04/22/2015 02:53 PM, Brandon Schwartz wrote: > And by blkreplay, I meant replay the blktrace with FIO > > On Wed, Apr 22, 2015 at 2:52 PM, Brandon Schwartz wrote: >> Is there an accurate way to capture idle time with blktrace? For >> example, if I run/trace the following FIO script: >> >> [global] >> direct=1 >> ioengine=libaio >> readwrite=read >> blocksizeQ2k >> filename=/dev/sdd >> >> [read] >> runtime >> name=read >> >> [read2] >> stonewall=1 >> startdelay@ >> runtime >> name=read2 >> >> And attempt to replay it using blkreplay, it will ignore the wait time >> and simply read for 20seconds instead of read 10s, wait for 40s, read >> 10s. replay_no_stall=1 -- Jens Axboe