Re: Failed reads from RAID-0 array; still no joy in Mudville.

[Bill Davidsen <davidsen@tmr.com>]

Michael Schwarz wrote:
> Update:
>
> (For those who've been waiting breathlessly). It hangs at a particular
> point in a particular file. In other words, it doesn't depend on the total
> number of bytes transfered. Rather, when it reaches a particular point in
> a particular file (12267520 bytes into a file that is 1073709056 bytes
> long) it hangs.
>   

I have an odd thought, have you tried copying that same file to 
/dev/null or similar? The reason I ask is that if it were by any chance 
a sparse file, while the program is reading all those unwritten bytes 
odd things may happen. Sorry, I haven't seen this is years, but I do 
remember seeing a filesystem on the destination end running out of space 
because all those unwritten pages were now being "really written" as zeros.

Use of cp with the --sparse= flag may change the behavior if this is the 
case.
> I begin to suspect that I have a "dead spot" in my USB hub. But what gets
> me if that is true is why does the write work? Do cp and dd not check to
> see if writes succeed?
>
> I know it isn't a particular flash drive because I've used two different
> sets of 7 USB drives and it seems to fail consistently no matter which.
>
> Nonetheless, I'm beginning to think I'm dealing with a hardware issue, not
> a kernel issue, just because it is so consistent.
>
> Thanks again for all the help.
>
>
>   


-- 
bill davidsen <davidsen@tmr.com>
  CTO TMR Associates, Inc
  Doing interesting things with small computers since 1979