2.4.18 kernels: no DMA w/ServerWorks LE chipsets
hahn at physics.mcmaster.ca
Fri Aug 2 10:23:21 EDT 2002
> enable DMA on ide-disk devices (under kernel 2.4.18-5smp, RedHat
it's worth noting that .18 is fairly ancient (though I suppose RH
may have back-ported the SW changes...) I just looked, and there
are some non-whitespace changes since .18.
AA also has the following in his patch cluster:
| Attempt to fix the ServerWorks problem sit certain disks and DMA.
| Author: Martin Wilck <Martin.Wilck at Fujitsu-Siemens.com>
> 2.4.18-5smp kernel ("hdparm -d1 /dev/hda") can lock up the system.
in general, hdparm should be considered dangerous in moder Linuxes.
> As a consequence, we get only 3.5-4.5 MB/s on these disks instead of
> 12-22 MB/s which should be the norm.
indeed 4.5 is bad; most modern IDEs deliver 25-45 MB/s (inner-outer).
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