At Fri, 12 Aug 2011 22:35:12 +0100 (BST) CentOS mailing list <centos at centos.org> wrote: > > On Fri, 12 Aug 2011, Robert Heller wrote: > > *snip* > > >>> The disk's *firmware* updated itself. So long as the *disk* is powered > >>> up and spinning, its *firmware* is 'running' (or runs when the disk is > >>> accessed or something like that). Modern disks are a long, long way > >>> from the simple MFM drives of the 1970s (which presented little more > >>> than a buffered interface to the drive mechanism and read/write heads > >>> to the host controller -- eg little more than a simple floppy disk > >>> drive) -- modern disks have actual embedded micro-processors on them > >>> doing various stuff, including monitoring and logging things like > >>> sector errors, drive temp., and so on. > >> > >> So does accessing some of the smart data cause any disk i/o > >> at all, or is this all done from directly firmware? > > > > Depends. Some of the SMART information is stored on special sectors of > > the platter (sectors that are not part of the sectors available for > > normal use). Some of the information is fixed burned into the > > (E*)ROM(s) (eg serial numbers) on the disk's logic board and some > > information is 'live' (eg current disk temperature). There IS I/O > > between the host system and the disk's logic board. > > Thanks Robert. Reason I ask is because I'm using GKrellM to > monitor my HDD temperatures. So I just wondered if querying > the HDD temps to often would create more disk i/o ? I believe the HDD temps are a 'live' sensor reading. The firmware might log record/excessive high temps to a reserved sector as part of the disk's long term health status, but it is unlikely to be constantly logging routine temperatures. > > Kind Regards, > > Keith Roberts > > ----------------------------------------------------------------- > Websites: > http://www.karsites.net > http://www.php-debuggers.net > http://www.raised-from-the-dead.org.uk > > All email addresses are challenge-response protected with > TMDA [http://tmda.net] > ----------------------------------------------------------------- > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos > > -- Robert Heller -- 978-544-6933 / heller at deepsoft.com Deepwoods Software -- http://www.deepsoft.com/ () ascii ribbon campaign -- against html e-mail /\ www.asciiribbon.org -- against proprietary attachments