From mboxrd@z Thu Jan 1 00:00:00 1970 From: Phillip Susi Subject: Re: [PATCH/RESEND v2 0/2] SATA disk resume time optimization Date: Mon, 11 Nov 2013 12:08:49 -0500 Message-ID: <52810F21.9070605@ubuntu.com> References: <20131017193331.GA11747@linux.intel.com> <527AF287.7020700@ubuntu.com> <20131109012023.GA8978@linux.intel.com> <527EA218.6010604@ubuntu.com> <20131111165920.GA25366@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from cdptpa-omtalb.mail.rr.com ([75.180.132.120]:62738 "EHLO cdptpa-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753784Ab3KKRIw (ORCPT ); Mon, 11 Nov 2013 12:08:52 -0500 In-Reply-To: <20131111165920.GA25366@linux.intel.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: todd.e.brandt@linux.intel.com Cc: linux-scsi@vger.kernel.org, linux-ide@vger.kernel.org, tj@kernel.org, JBottomley@parallels.com -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 11/11/2013 11:59 AM, Todd E Brandt wrote: > 500ms is actually quite alot when you compare it with android or > iOS, or even with other subsystems like USB. USB is the second > worst offender after SATA disks and it tends to take around 600ms > for most standard systems with an onboard webcam, and with other > devices plugged in ever longer. I think we should optimize out > every millisecond we can. I think you missed my point: if the disk is going to be started in 9000ms vs 8500ms, it doesn't make much difference, and I think in practice the difference will be less than that. I don't think it is worth requiring that all disks start up to save a few percent in the cases where the disk is required ( and I'm not clear that there even are any such cases ). > You mentioned that you tuned your system to remove all cases that > trigger non-essential disk wakeups, and that works great for you, > but it won't help anyone using fedora or OpenSUSE or Yocto, etc. > And even if you could formallize your changes to Ubuntu to create a > fully optimized user space, you're still at the mercy of the user's > install choices, which can quickly throw a wrench in the works. No, I did not tune my system; I fixed the kernel so that userspace's activities do not start those disks. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.17 (MingW32) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBAgAGBQJSgQ8hAAoJEJrBOlT6nu75c04H/2ej9NzdyrWkuPv2SLGgb51Y iBmeAkJEoFXwgu0UCZ2Ty3dpUkW7jcRiKKv5q8d1Anj4eGFIpx+CjUptCE3MCs1w PWQm7uB6+DgOhj3aqF9DulBx0Yp3+gISwOTXYLAIirIReE4Vk904ZuYHo4IvJmug vbk4p6n5iGLMqV/QFsymPoOFtUzKQPHj4YDL3Piu0fse8AOIHk5BJtmmtj1YbAck oAsMIYz6UQZ2tXpzxcy1ISgZYUO8k6CcrXg8WE2ws9gZLNJtBHniLC1t2VCE10KF BSzP+tgN+Glbk+HyJUuwjALa/CkFk9FKQJT8LJQfn0rRhjku/vZXsZoFgCQiIx0= =THLl -----END PGP SIGNATURE-----