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Amen!
Thanks
TC


On 11/15/04 12:59 PM, "Jeff Garzik" <[EMAIL PROTECTED]> wrote:

> Pat LaVarre wrote:
>> Jeff G:
>> 
>>>> In reading the proposal, it seems that there is a issue. Enough so
>>>> the write
>>>> a proposal. If the state does occur as the proposal describes, then
>>>> the bad data is read
>>>> to clear the DRQ. A performance issue and as you comment, issue a
>>>> soft reset
>>>> and re-issue the command. How long does a soft reset take
>>>> (performance hit).
>>> 
>>> 
>>> When you are getting into error states, you may assume that
>>> performance has _already_ gone out the window.
>>> 
>>> When writing error handling code, focus on _correctness_ not
>>> performance IMO.
>> 
>> 
>> In principle I agree ... except for when correctness and performance
>> become available together, I also remember anecdotes like USB DVD/CD
>> burners creating coasters because the host handling of unexpectedly
>> short data was slow, and HDD appearing slower in one operating system
>> than another, because one of the operating systems covered up
>> non-repeating errors more rapidly ...
>> 
>> Does your personal history of pain include no such episodes?
> 
> Pardon the use of exclamation points, I normally abstain from the
> practice, but:  we are talking about error handling here!
> 
> We don't need every ATA driver stack "optimizing" its error handling.
> We need to encourage software authors to write software that handles
> errors in the same, boring manner as everyone else.
> 
> We're not talking about data transfer here.
> Data transfer is the hot path, the part you optimize.
> 
> Error handling is the 0.1% case that you _must_ get right.  Performance
> considerations do nothing but increase complexity.  You get the
> performance that correctness provides, and nothing more :)
> 
> Jeff
> 
> 


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