Re: Quick question about libata and hdparm

["Rogério Brito" <rbrito@ime.usp.br>]

Hi, Jeff.

On Apr 19 2009, Jeff Garzik wrote:
> Michael Tokarev wrote:
>> Well, the kernel does a good job here in *almost* all cases.
>> The problematic case is when a device has some bad/unreadable
>> blocks/sectors.  When such a place occurs on read, libata
>> (or whatever it is) performs several retries, each time
>> using "less aggressive" settings - like reducing UDMA and
>> PIO mode till the lowest possible PIO/33.  And the device
>> stays in that mode until reboot, even if the problematic
>> sector has been relocated.  So it'd be nice to be able to
>> reset the mode back in such cases.
>
> Do you have a log?

I have a log here of libata reducing UDMA speed. I don't know if this is
any hardware problem or not (I think not), but I do see libata
complaining and reducing the speed of the drive.

Would you like it?


Thanks,

-- 
Rogério Brito : rbrito@{mackenzie,ime.usp}.br : GPG key 1024D/7C2CAEB8
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