#2278 BLOC Future : Memory pressure

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#2278: Memory pressure
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  Reporter:  cjb          |       Owner:  cjb           
      Type:  defect       |      Status:  new           
  Priority:  blocker      |   Milestone:  Future Release
 Component:  performance  |     Version:                
Resolution:               |    Keywords:                
  Verified:  0            |    Blocking:                
 Blockedby:               |  
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Changes (by tomeu):

 * cc: tomeu (added)


Comment:

 Replying to [comment:18 gnu]:
 > I believe that much of the slowness of MP machines in Ship.1 is due to
 memory pressure.  When a page is paged in from a shared library, the file
 system needs to uncompress it (this is not quick).  It is quickly thrown
 away due to memory pressure, and then needs to be re-read and re-
 uncompressed.  Because we are not using prelink, many shared library pages
 are modified by relocation/linkage and thus pollute the RAM and can never
 be swapped out, reducing the available page frames for read-only pages.
 See /proc/NNNNN/smaps for details.

 Would be nice to know when the kernel decides to throw away one of those
 pages. Do you know of an easy way to log that?

-- 
Ticket URL: <http://dev.laptop.org/ticket/2278#comment:19>
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