Adam Carter <adamcart...@gmail.com> wrote:
> I have 1 ssd and 2 spinners in a system. hdparm reports that
> multcount=0, and hdparm -i reports MultSect=off on the ssd (only).
>
> Are mulitcount and MultiSect the same thing?
It seems to be the same (see below).
> Why would it be disabled by default on the ssd?
From hdparm manpage:
"Some drives claim to support multiple mode, but lose data at some
settings. Under rare circumstances, such failures can result in
massive filesystem corruption."
I was curious and tried to enable it on my ssd:
computer ~ # /sbin/hdparm -i /dev/sda
/dev/sda:
Model=Corsair CSSD-F60GB2, FwRev=2.0, SerialNo=10416510350009990139
Config={ Fixed }
RawCHS=16383/16/63, TrkSize=0, SectSize=0, ECCbytes=4
BuffType=unknown, BuffSize=unknown, MaxMultSect=16, MultSect=off
CurCHS=16383/16/63, CurSects=16514064, LBA=yes, LBAsects=117231408
IORDY=on/off, tPIO={min:120,w/IORDY:120}, tDMA={min:120,rec:120}
PIO modes: pio0 pio1 pio2 pio3 pio4
DMA modes: mdma0 mdma1 mdma2
UDMA modes: udma0 udma1 udma2 udma3 udma4 udma5 *udma6
AdvancedPM=no WriteCache=enabled
Drive conforms to: unknown: ATA/ATAPI-2,3,4,5,6,7
* signifies the current active mode
computer ~ # /sbin/hdparm -m 16 /dev/sda
/dev/sda:
setting multcount to 16
Use of -m is VERY DANGEROUS.
Only the old IDE drivers work correctly with -m with kernels up to at least
2.6.29.
libata drives may fail and get hung if you set this flag.
Please supply the --yes-i-know-what-i-am-doing flag if you really want this.
Program aborted.
I cowardly decided that it is better to leave it off, because I think that I
really doesn't know what I am doing. ;-)
If you are braver then I am, then please report your experiences. :-)
--
Regards
wabe
