#10112 NORM Not Tri: GUI freezes on fsync

[Zarro Boogs per Child]

#10112: GUI freezes on fsync
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           Reporter:  jon.nettleton  |       Owner:                                   
               Type:  defect         |      Status:  new                              
           Priority:  normal         |   Milestone:  Not Triaged                      
          Component:  not assigned   |     Version:  Development build as of this date
         Resolution:                 |    Keywords:                                   
        Next_action:  never set      |    Verified:  0                                
Deployment_affected:                 |   Blockedby:                                   
           Blocking:                 |  
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Comment(by jon.nettleton):

 Some where along the line the kernel thinks that our SD card is a lot
 faster than it is.  Looking at these timed dd commands we see the internal
 card reports a higher throughput but takes over twice as long to complete.
 I can definitely see where this would cause the jerky system performance
 on writes.


 {{{
 Internal SD:

 time sh -c "dd if=/dev/zero of=ddfile bs=8k count=2000 && sync"
 2000+0 records in
 2000+0 records out
 16384000 bytes (16 MB) copied, 0.14648 s, 112 MB/s

 real    0m14.982s
 user    0m0.000s
 sys     0m0.200s
 }}}


 {{{
 External SD:

 time sh -c "dd if=/dev/zero of=ddfile bs=8k count=2000 && sync"
 2000+0 records in
 2000+0 records out
 16384000 bytes (16 MB) copied, 0.169331 s, 96.8 MB/s

 real    0m6.100s
 user    0m0.000s
 sys     0m0.200s
 }}}

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Ticket URL: <http://dev.laptop.org/ticket/10112#comment:2>
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