#9455 NORM 1.5-F11: maybe use data=ordered for root mount

[Zarro Boogs per Child]

#9455: maybe use data=ordered for root mount
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           Reporter:  cjb        |       Owner:  cjb                              
               Type:  defect     |      Status:  new                              
           Priority:  normal     |   Milestone:  1.5-F11                          
          Component:  distro     |     Version:  Development build as of this date
         Resolution:             |    Keywords:                                   
        Next_action:  never set  |    Verified:  0                                
Deployment_affected:             |   Blockedby:                                   
           Blocking:             |  
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Changes (by Quozl):

  * version:  not specified => Development build as of this date
  * component:  not assigned => distro


Comment:

 Related to #9612 which describes Sugar's response to zero-filled or
 uninitialised files after a crash.

 ''data=writeback'' is what we are using on os40.  mount(8) says this is
 ''rumoured to be the highest-throughput option''.  This rumour may be true
 only for storage with a rotational latency.

 ''data=ordered'' is the default for mount(8), and other systems use this
 as the default, and it would have hidden the symptom in #9612.
 Applications seem to be written to match this common behaviour.  It is
 effectively how jffs2 on 802 worked as well.

 I'm ambivalent.  It's a huge debate, plenty of community discussion,
 especially around ext4 and solid state disks.

 We could also consider fiddling with ''commit=nrsec'' ... or add a
 ''sync'' to the system's response to a power button down event, so that a
 user forced power down would be preceeded with an attempt to write data to
 the SD.

-- 
Ticket URL: <http://dev.laptop.org/ticket/9455#comment:2>
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