#11472 NORM 1.75-so: Try out 8-bit bus width on eMMC

[Zarro Boogs per Child]

#11472: Try out 8-bit bus width on eMMC
---------------------------------+------------------------------------------
           Reporter:  cjb        |       Owner:  Quozl        
               Type:  defect     |      Status:  new          
           Priority:  normal     |   Milestone:  1.75-software
          Component:  kernel     |     Version:  not specified
         Resolution:             |    Keywords:               
        Next_action:  never set  |    Verified:  0            
Deployment_affected:             |   Blockedby:               
           Blocking:             |  
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Comment(by Quozl):

 Conclusion: no performance impact.  Performance follows eMMC chip.

 Test method:
 {{{
 fs-update
 boot
 telinit 1
 time badblocks -sv /dev/mmcblk0p1
 time badblocks -sv /dev/mmcblk0p2
 }}}

 Test results:
 {{{
 xo-1.75 b1 os11 ga104b4f mmcblk0p1 3.24 sec
 xo-1.75 b1 os11 184b134 mmcblk0p1 3.24 sec
 xo-1.75 b1 os11 184b134 mmcblk0p1 3.22 sec
 xo-1.75 b1 os11 184b134 mmcblk0p1 3.23 sec

 xo-1.75 c1 sku201 os11 184b135 mmcblk0p1 2.35 sec
 xo-1.75 c1 sku201 os11 184b135 mmcblk0p1 2.37 sec
 xo-1.75 c1 sku202 os11 ga104b4f mmcblk0p1 3.23 sec

 xo-1.75 b1 os11 ga104b4f mmcblk0p2 3 min 0.86 sec
 xo-1.75 b1 os11 184b134 mmcblk0p2 3 min 1.08 sec
 xo-1.75 b1 os11 184b134 mmcblk0p2 3 min 1.43 sec

 xo-1.75 c1 sku202 os11 ga104b4f mmcblk0p2 2 min 51.23 sec
 xo-1.75 c1 sku202 os11 ga104b4f mmcblk0p2 2 min 52.35 sec
 xo-1.75 c1 sku202 os11 ga104b4f mmcblk0p2 2 min 51.89 sec

 xo-1.75 c1 sku201 os11 184b135 mmcblk0p2 2 min 9.39 sec
 xo-1.75 c1 sku201 os11 184b135 mmcblk0p2 2 min 9.43 sec
 xo-1.75 c1 sku201 os11 184b135 mmcblk0p2 2 min 10.16 sec
 }}}

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Ticket URL: <http://dev.laptop.org/ticket/11472#comment:1>
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