#10040 NORM 11.2.0-: we don't use all available SD card space

[Zarro Boogs per Child]

#10040: we don't use all available SD card space
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           Reporter:  wad           |       Owner:  cjb                              
               Type:  defect        |      Status:  new                              
           Priority:  normal        |   Milestone:  11.2.0-M3                        
          Component:  build-system  |     Version:  Development build as of this date
         Resolution:                |    Keywords:                                   
        Next_action:  diagnose      |    Verified:  0                                
Deployment_affected:                |   Blockedby:                                   
           Blocking:                |  
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Changes (by dsd):

 * cc: dsd (added)


Comment:

 I suspect the time needed and impact on system performance during resize
 is mostly because the process has to zero out a load of inode tables.

 John Gilmore notes that new kernels have an option to defer the inode
 table zeroing until much later:

 {{{
 There's now a mkfs option that doesn't zero all the inodes while
 building the file system.  It instead sets an extent for the inode
 tables, in the superblock, and the kernel zeroes more inodes as it
 needs to, in parallel with ordinary system operation.  It also has a
 similar option for the block groups.  This is the lazy_itable_init
 option set with mke2fs -E and the uninit_bg option set with mke2fs -O.

 uninit_bg works only with ext4.  I think lazy_itable_init works with
 ext3.
 }}}

 This may make resize a much quicker and cheaper operation.

-- 
Ticket URL: <http://dev.laptop.org/ticket/10040#comment:20>
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