Messages in this thread | | | From | John Bradford <> | Subject | Re: Benefits from computing physical IDE disk geometry? | Date | Sun, 13 Apr 2003 10:51:19 +0100 (BST) |
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> Any good SCSI drive knows the physical geometry of the disk and can > therefore optimally schedule reads and writes. Although necessary features, > like read queueing, are also available in the current SATA spec, I'm not > sure most drives will implement it, at least not very well. > > So, what if one were to write a program which would perform a bunch of > seek-time tests to estimate an IDE disk's physical geometry? It could then > make that information available to the kernel to use to reorder accesses > more optimally. Additionally, discrepancies from expected seek times could > be logged in the kernel and used to further improve efficiency over time.
On a system that's been set up with one large root partition, and nothing else, you might get a noticable gain, but I would guess that you could get a simliar gain by partitioning the disk and manually placing, E.G. /var near the outside of the disk, and things like /etc near the centre. I.E. placing more active partitions on faster areas of the disk.
> If it were good enough, many of the advantages of using SCSI disks would > become less significant.
Not really - there are still a lot of advantages of SCSI that it wouldn't address.
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