Date: Thu, 5 Apr 2012 16:58:20 +0200 From: Gary Jennejohn <gljennjohn@googlemail.com> To: Alexander Leidinger <Alexander@Leidinger.net> Cc: freebsd-hackers <freebsd-hackers@freebsd.org>, Jerry Toung <jrytoung@gmail.com> Subject: Re: CAM disk I/O starvation Message-ID: <20120405165820.38698f1f@ernst.jennejohn.org> In-Reply-To: <20120405052246.00002c53@unknown> References: <CADC0LV=-e%2B7PshRQdc69e2-Vktf6XFpVrqiMpx=QL4m_%2B9hSnw@mail.gmail.com> <20120403193124.46ad9de9@ernst.jennejohn.org> <CADC0LVm1HY2Dz%2BVk_GK35szRS6ySviLhMiL1TSRBOnPwQnBwRg@mail.gmail.com> <20120405052246.00002c53@unknown>
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On Thu, 5 Apr 2012 05:22:46 +0200 Alexander Leidinger <Alexander@Leidinger.net> wrote: > On Tue, 3 Apr 2012 14:27:43 -0700 Jerry Toung <jrytoung@gmail.com> > wrote: > > > On 4/3/12, Gary Jennejohn <gljennjohn@googlemail.com> wrote: > > > > > It would be interesting to see your patch. I always run HEAD but > > > maybe I could use it as a base for my own mods/tests. > > > > > > > Here is the patch > > This looks fair if all your disks are working at the same time (e.g. > RAID only setup), but if you have a setup where you have multiple > disks and only one is doing something, you limit the amount of tags > which can be used. No idea what kind of performance impact this would > have. > > What about the case where you have more disks than tags? > > I also noticed that you do a strncmp for "da". What about > "ada" (available in 9 and 10), I would assume it suffers from the same > problem. > It seems to. All my disks are ada. -- Gary Jennejohn
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