Re: mpt Serious performance issues

[Stephan <stephanwib%googlemail.com@localhost>]

Hi all,

some new findings on this issue:

-The OpenBSD driver for this chip is called mpi and performs better
(Write speed ~35MB/s, Read speed ~70 MB/s).

-Speking of write caching, the NetBSD driver does not seem to have
code which could activate it. There is a bit defined in mpt_mpilib.h
which could be set in some kind of settings page
(_RAID_VOL0_SETTINGS):

#define MPI_RAIDVOL0_SETTING_WRITE_CACHING_ENABLE       (0x0001)

-The OpenBSD driver has a function to (de)activate the write caching
called mpi_ioctl_cache() (see:
http://www.openbsd.org/cgi-bin/cvsweb/~checkout~/src/sys/dev/ic/mpi.c?rev=1.165;content-type=text%2Fplain
). How would this be implemented in NetBSD? As a hack for testing,
does anybody see a chance to hard-code this bit-setting into the
driver?

Regards,

Stephan