#10559 HIGH 1.75-so: XO-1.75 os2 corrupting large files (was: XO-1.75 / OS2 has problems with corrupting large files)

[Zarro Boogs per Child]

#10559: XO-1.75 os2 corrupting large files
---------------------------------+------------------------------------------
           Reporter:  wad        |       Owner:  buytenh                          
               Type:  defect     |      Status:  new                              
           Priority:  high       |   Milestone:  1.75-software                    
          Component:  kernel     |     Version:  Development build as of this date
         Resolution:             |    Keywords:                                   
        Next_action:  reproduce  |    Verified:  0                                
Deployment_affected:             |   Blockedby:                                   
           Blocking:             |  
---------------------------------+------------------------------------------

Comment(by Quozl):

 Reproduced on XO-1.75 with cardboard tag number 2.

 Summary: random single and double bit clears at a rate of one in 281325
 bits.

 Detail.

 Used scp to copy an 825 MB file over wireless to SD.  Repeated the copy to
 a different file name.  Ran md5sum on the desktop computer, and on the
 XO-1.75, got three different md5sums.  Repeated md5sum and got the same
 md5sums.

 {{{
 scp file laptop:a
 scp file laptop:b
 md5sum file
 ssh laptop md5sum a b
 }}}

 Repeated one copy and got different md5sum for the new copy.

 {{{
 scp file laptop:a
 ssh laptop md5sum a b
 }}}

 The problem reduced in frequency as the test file size shrank.

 The problem was less frequency for text, more frequent for binary files.

 The problem vanished after some hours of testing, and came back after a
 reboot.

 Using a file constructed from Sugar source code and repeatedly
 concatenated, then copied over wireless, then copied back and subjected to
 diff(1) ... the cause of the md5sum differences are single and double bit
 clears in the data, at a rate of roughly 11 in 328 MB, or one in 281325
 bits.

 Slice of diff(1) output:

 {{{
 @@ -1954905,7 +1954905,7 @@
    1. You may copy and distribute verbatim copies of the Program's
  source code as you receive it, in any medium, provided that you
  conspicuously and appropriately publish on each copy an appropriate
 -copyright notice and disclaimer of warranty; keep intact all the
 +copyright notice and disclaimer of warranty; kedp intact all the
  notices that refer to this License and to the absence of any warranty;
  and give any other recipients of the Program a copy of this License
  along with the Program.
 @@ -3638483,7 +3638483,7 @@
      Change emulator resolution to 800x600.
      Change canvas resolution to 1200x900, scale it down in the emulator.

 -commit 7dddefe22902fd671fdcac19da83aa7c6874b065
 +`ommit 7dddefe22902fd671fdcac19da83aa7c6874b065
  Merge: 115eefb 9ad1fe6
  Author: Marco Pesenti Gritti <marco at localhost.localdomain>
  Date:   Wed Aug 16 19:55:34 2006 +0200
 }}}

-- 
Ticket URL: <http://dev.laptop.org/ticket/10559#comment:2>
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