#2517 HIGH First D: Optimize verification of live incremental upgrades

[Zarro Boogs per Child]

#2517: Optimize verification of live incremental upgrades
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  Reporter:  cscott           |       Owner:  mstone                
      Type:  enhancement      |      Status:  new                   
  Priority:  high             |   Milestone:  First Deployment, V1.0
 Component:  upgrade utility  |     Version:                        
Resolution:                   |    Keywords:                        
  Verified:  0                |  
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Comment(by cscott):

 Times with libtomcrypt, compiled with gcc-4.3 -march=geode -O9:

 * SHA+RMD:  5m17s (3m 5s user)
 * SHA only: 4m 1s (1m56s user)
 * RMD only: 3m 7s (1m11s user)
 * no hash:  2m 9s (   2s user)

 Note that my system times are significantly larger on this run, probably
 because I yum installed some stuff (gcc, etc) on my XO, so the filesystem
 size is larger and JFFS2 is having to work harder.

 Compiling with -march=geode -O2 (since it's possible that -O9 creates
 suboptimal code) yields:

 * SHA+RMD: 5m12s (3m9s user)

 So we might as well compile with -O2.

 So, libtomcrypt yields a little benefit for RIPEMD-160, but a decent
 amount of SHA256 improvement.  It's worth using.

-- 
Ticket URL: <https://dev.laptop.org/ticket/2517#comment:9>
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