From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from averel.grnet-hq.admin.grnet.gr ([195.251.29.3]:46991 "EHLO averel.grnet-hq.admin.grnet.gr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751487Ab3HTH4T (ORCPT ); Tue, 20 Aug 2013 03:56:19 -0400 Message-ID: <52131CC5.9020508@grnet.gr> Date: Tue, 20 Aug 2013 10:37:41 +0300 From: Alex Pyrgiotis MIME-Version: 1.0 Subject: Re: Using LFSR References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: fio-owner@vger.kernel.org List-Id: fio@vger.kernel.org To: Juan Casse Cc: "fio@vger.kernel.org" On 08/20/2013 02:11 AM, Juan Casse wrote: > Hi, > > How is LFSR used? > > When running the job file: > > [global] > readwrite=randwrite > size=64k > bs=8192 > random_generator=lfsr > [test_job] > > fio returns: > > "fio: failed allocating random map. If running a large number of jobs, > try the 'norandommap' option or set 'softrandommap'. Or give a larger > --alloc-size to fio." > > I tried the recommendations in the message above to no avail. I also > tried other combinations of size, bs, and readwrite. Hi Juan, Could you provide the fio version you are using (fio -v)? I'm currently using the latest version from git and I don't see these results. Specifically, what I'm getting is: ------------------------------- test_job: (g=0): rw=randwrite, bs=8K-8K/8K-8K/8K-8K, ioengine=sync, iodepth=1 fio-2.1.2-13-g3e10 Starting 1 process Value is 7 Value is 6 Value is 4 Value is 0 Value is 1 Value is 5 Value is 2 Value is 3 test_job: (groupid=0, jobs=1): err= 0: pid=24672: Tue Aug 20 10:27:28 2013 write: io=65536B, bw=64000KB/s, iops=8000, runt= 1msec clat (usec): min=6, max=43, avg=11.50, stdev=12.75 lat (usec): min=7, max=44, avg=11.88, stdev=12.99 clat percentiles (usec): <...snip...> lat (usec) : 10=87.50%, 50=12.50% cpu : usr=0.00%, sys=0.00%, ctx=16, majf=0, minf=41 <...snip...> Run status group 0 (all jobs): WRITE: io=64KB, aggrb=64000KB/s, minb=64000KB/s, maxb=64000KB/s, mint=1msec, maxt=1msec Disk stats (read/write): sda: ios=0/0, merge=0/0, ticks=0/0, in_queue=0, util=0.00% ------------------------------- The output has been cut in some parts for readability reasons. Also, the "Value is..." lines have been added to show which blocks fio is hitting. Regards, Alex -- Alex | apyrgio@grnet.gr