Does WD driver support MaxMultSect=16, and is it safe for a mysql server?

[bbb <linuzboy@gmail.com>]

My WD driver `hdparm -i` shows thatt it support multiple sector I/O
and MaxMultSect=16. But the hdparm manual shows that the value can not
be set too large especially for WD driver, or it will corrupt the file
system.

Does your drivers set the hdparm -m16 to speed up driver r/w
operations, especially when your driver is WD. Because I am running a
mysql service, and database r/w ability is very important.

shell >man hdparm
...
Some    drives, however (most notably the WD Caviar series), seem to run
             slower with multiple mode enabled.  Your mileage may vary.  Most
             drives support the minimum settings of 2, 4, 8, or 16 (sectors).
             Larger settings may also be possible, depending on the drive.  A
             setting of 16 or 32 seems optimal on many systems.  Western Dig-
             ital recommends lower settings of  4  to  8  on  many  of  their
             drives,  due tiny (32kB) drive buffers and non-optimized buffer-
             ing algorithms.  The -i flag can be used  to  find  the  maximum
             setting supported by an installed drive (look for MaxMultSect in
             the output).  Some drives claim to support  multiple  mode,  but
             lose  data  at  some  settings.   Under rare circumstances, such
             failures can result in massive filesystem corruption.
.......


shell> hdparm -i /dev/hdb

/dev/hdb:

Model=WDC WD400EB-75CPF0, FwRev=06.04G06, SerialNo=WD-WMAATC433661
Config={ HardSect NotMFM HdSw>15uSec SpinMotCtl Fixed DTR>5Mbs FmtGapReq }
RawCHS=16383/16/63, TrkSize=57600, SectSize=600, ECCbytes=40
BuffType=DualPortCache, BuffSize=2048kB, MaxMultSect=16, MultSect=off
CurCHS=16383/16/63, CurSects=16514064, LBA=yes, LBAsects=78165360
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
AdvancedPM=no WriteCache=enabled
Drive conforms to: Unspecified:  ATA/ATAPI-1 ATA/ATAPI-2 ATA/ATAPI-3
ATA/ATAPI-4 ATA/ATAPI-5

* signifies the current active mode

Does WD driver support MaxMultSect=16, and is it safe for a mysql server?


Thanks....