serial ATA status?

[George Georgalis]

On Fri, Nov 05, 2004 at 12:20:14PM -0800, Matthew Dillon wrote:
>
>:Under Linux IDE is deprecated for SCSI to control SATA. Will using IDE
>:affect SATA performance or reliability? or is SCSI the preferred api
>:only for linux?
>:
>:// George
>:
>:-- 
>:George Georgalis, systems architect, administrator Linux BSD IXOYE
> 
>    That doesn't really have anything to do with it.  Even Linux's SCSI
>    driver is talking the ATAPI/IDE protocol to the SATA device.
>
>					-Matt


I've looked at the scsi/sata_sil.c driver but I learned more C than I
understood what was actually happening.

My main concern is 15 byte write quirk that seems to only affect certain
combinations of drives and the 3112 (Addonics) controller.

My drive in particular, was subject to serious corruption until about
linux-2.6.7-bk8 when it was fixed. However, my drive got added to the
black list which means ~20Mb/sec vs ~50Mb/sec. It doesn't belong in the
blacklist, when I remove it, I get the performance with no corruption
issues. I've tested a lot of gigs on that 160G drive and made it my
primary disk about the time 2.6.8.1 came out with the following mod:

linux-2.6.8.1-sta/drivers/scsi/sata_sil.c
. ..
struct sil_drivelist {
        const char * product;
        unsigned int quirk;
} sil_blacklist [] = {
        { "ST320012AS",         SIL_QUIRK_MOD15WRITE },
        { "ST330013AS",         SIL_QUIRK_MOD15WRITE },
        { "ST340017AS",         SIL_QUIRK_MOD15WRITE },
        { "ST360015AS",         SIL_QUIRK_MOD15WRITE },
        { "ST380023AS",         SIL_QUIRK_MOD15WRITE },
        { "ST3120023AS",        SIL_QUIRK_MOD15WRITE },
        /*{ "ST3160023AS",        SIL_QUIRK_MOD15WRITE },*/
        { "ST340014ASL",        SIL_QUIRK_MOD15WRITE },
        { "ST360014ASL",        SIL_QUIRK_MOD15WRITE },
        { "ST380011ASL",        SIL_QUIRK_MOD15WRITE },
        { "ST3120022ASL",       SIL_QUIRK_MOD15WRITE },
        { "ST3160021ASL",       SIL_QUIRK_MOD15WRITE },
        { "Maxtor 4D060H3",     SIL_QUIRK_UDMA5MAX },
        { }
};


I've not tried sata on 2.6.9, but I don't expect any
difference.

Of course I'm only saying all this because it is a
nasty bug that I hope doesn't show up in DragonFly.

// George


-- 
George Georgalis, systems architect, administrator Linux BSD IXOYE
http://galis.org/george/ cell:646-331-2027 mailto:george at xxxxxxxxx