Re: [drivers][sata-promise] TX4 has the cache enabled, it should be disabled

[Jeff Garzik <jgarzik@pobox.com>]

MALET JL wrote:
> hello,
> I've a TX4 150 card and encounter the following effects :
> ->"shorts" files (<1Mo) are copied at 35Mo/s av
> ->"long" files (>1Mo) are "burst" copied (ie a big "burst" then hangs, 
> burst, hangs) this has the following effects :
> 1) average fall back to 12Mo/s
> 2) systems "hangs" (mouse, keyboard behave like a 100% used cpu) but cpu 
> usage is still slow
> 3) mplayer reset the streams every second (cpu usage still low)
> 
> this is 1-2 week that I have this issue, but can't find where it comes 
> from...... yesterday by chance when I loaded sata-promise I noticed 
> "write through" this remembered be some issue I go when I first had the 
> sata board, making a short research made me remember :
> 
> DISABLE THE BOARD CACHE! on windows this is the same when cache is 
> enabled : performance drops, system interactive is awfull....


There is no on-board cache on the TX4.

Further, you are thinking about the SCSI layer's caching support, i.e. 
basically whether the driver supports SYNCHRONIZE CACHE (aka 
flush-cache) scsi command.

	Jeff