Date: Fri, 20 Mar 2009 07:48:33 +0000 From: Bruce Cran <bruce@cran.org.uk> To: "Poul-Henning Kamp" <phk@phk.freebsd.dk> Cc: freebsd-current@freebsd.org, Andriy Gapon <avg@icyb.net.ua> Subject: Re: ata: printf on every spinup/spindown? Message-ID: <20090320074833.67d615e2@gluon> In-Reply-To: <10611.1237233778@critter.freebsd.dk> References: <49BE7C5A.2080103@icyb.net.ua> <10611.1237233778@critter.freebsd.dk>
next in thread | previous in thread | raw e-mail | index | archive | help
On Mon, 16 Mar 2009 20:02:58 +0000 "Poul-Henning Kamp" <phk@phk.freebsd.dk> wrote: > In message <49BE7C5A.2080103@icyb.net.ua>, Andriy Gapon writes: > > >I am playing with ata spindown feature and I think that it is really > >unnecessary to print a message each time ata driver is going to > >spindown a disk or let it be spinned up: > >ad6: Idle, spin down > >ad6: request while spun down, starting. > >ad6: drive spun down. > >ad6: Idle, spin down > >ad6: request while spun down, starting. > > The reason I added the printf was to make it very annoying. > > Spinning a disk up and down too often wears it out much faster than > leaving it running. > > In general you do not want to spin a disk down unless it is going to > stay spun down for at least 15-30 minutes. > > If dmesg is going to spin your disk up, then it will wake up every 5 > minutes due to the atrun message and you are clearly doing it wrong. > Related to this, the ATA driver should probably have some means, either automatically or via atacontrol, of setting the APM value on disks; I bought a new laptop and immediately had to install sysutils/ataidle in order to stop the heads loading/unloading several times per minute by setting APM to 254. Apparently it's fairly common for laptop drives to have overly aggressive power settings that need intervention from the OS. -- Bruce Cran
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20090320074833.67d615e2>