Messages in this thread | | | Date | Fri, 09 Apr 2010 08:56:04 -0700 (PDT) | From | Ben Gamari <> | Subject | Re: 32GB SSD on USB1.1 P3/700 == ___HELL___ (2.6.34-rc3) |
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On Thu, 8 Apr 2010 22:35:26 +0200, Andreas Mohr <andi@lisas.de> wrote: > On Thu, Apr 08, 2010 at 04:12:41PM -0400, Bill Davidsen wrote: > > Andreas Mohr wrote: > >> Clearly there's a very, very important limiter somewhere in bio layer > >> missing or broken, a 300M dd /dev/zero should never manage to put > >> such an onerous penalty on a system, IMHO. > >> > > You are using a USB 1.1 connection, about the same speed as a floppy. If > > Ahahahaaa. A rather distant approximation given a speed of 20kB/s vs. 987kB/s ;) > (but I get the point you're making here) > > I'm not at all convinced that USB2.0 would fare any better here, though: > after all we are buffering the file that is written to the device > - after the fact! > (plus there are many existing complaints of people that copying of large files > manages to break entire machines, and I doubt many of those were using > USB1.1) > https://bugzilla.kernel.org/show_bug.cgi?id=13347 > https://bugzilla.kernel.org/show_bug.cgi?id=7372 > And many other reports.
Indeed. I have found this to be a persistent problem and I really wish there were more interest in debugging this. I have tried bringing the community's resources to bear on this issue several[1] times, and each time we fail to get enough of the right eyes looking at it or developer interest simply vanishes.
I've started putting together a list[2] of pertinent threads/patches/bugs/data in hopes that this will lower the energy barrier of getting up to speed on this issue. Hopefully this will help.
Cheers,
- Ben
[1] https://bugzilla.kernel.org/show_bug.cgi?id=12309 [2] http://goldnerlab.physics.umass.edu/wiki/BenGamari/IoWaitLatency
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