#8313 NORM 9.1.0: Can OFW save-nand be made to go faster?

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#8313: Can OFW save-nand be made to go faster?
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   Reporter:  thomaswamm           |       Owner:  wmb at firmworks.com                
       Type:  enhancement          |      Status:  new                              
   Priority:  normal               |   Milestone:  9.1.0                            
  Component:  ofw - open firmware  |     Version:  Development build as of this date
 Resolution:                       |    Keywords:                                   
Next_action:  communicate          |    Verified:  0                                
  Blockedby:                       |    Blocking:                                   
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Comment(by wmb at firmworks.com):

 Hmmm, here's another idea.  I wonder if the USB devices that exhibit slow
 write performance have been reformatted with filesystem parameters that
 don't work well with the underlying page size of the NAND FLASH chip
 inside?  NAND FLASH is tricky to handle well.  USB FLASH sticks have an
 internal microprocessor that translates between the conventional disk
 block paradigm and the NAND FLASH chip characteristics.  That translation
 is more efficient if the filesystem cluster size is a good match for the
 NAND page and erase block size.

 Such devices are factory-formatted with a suitable filesystem layout.
 It's common practice in the FOSS community to reformat hard disks using
 Linux tools like FDISK and mkfs.  That works well with hard disks, but is
 dodgy for FLASH storage, since you don't know what optimizations the
 internal microprocessor is doing based on assumptions of cluster sizes,
 FAT table locations, etc.

 My best results with USB keys have always been with devices where I left
 the factory filesystem format intact.

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Ticket URL: <http://dev.laptop.org/ticket/8313#comment:5>
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