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+** ZCACHE PLAN FOR PROMOTION FROM STAGING **
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+Last updated: Feb 13, 2013
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+
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+PLAN STEPS
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+
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+1. merge zcache and ramster to eliminate horrible code duplication
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+2. converge on a predictable, writeback-capable allocator
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+3. use debugfs instead of sysfs (per akpm feedback in 2011)
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+4. zcache side of cleancache/mm WasActive patch
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+5. zcache side of frontswap exclusive gets
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+6. zcache must be able to writeback to physical swap disk
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+ (per Andrea Arcangeli feedback in 2011)
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+7. implement adequate policy for writeback
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+8. frontswap/cleancache work to allow zcache to be loaded
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+ as a module
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+9. get core mm developer to review
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+10. incorporate feedback from review
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+11. get review/acks from 1-2 additional mm developers
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+12. incorporate any feedback from additional mm reviews
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+13. propose location/file-naming in mm tree
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+14. repeat 9-13 as necessary until akpm is happy and merges
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+
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+STATUS/OWNERSHIP
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+
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+1. DONE as part of "new" zcache; in staging/zcache for 3.9
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+2. DONE as part of "new" zcache (cf zbud.[ch]); in staging/zcache for 3.9
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+ (this was the core of the zcache1 vs zcache2 flail)
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+3. DONE as part of "new" zcache; in staging/zcache for 3.9
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+4. DONE (w/caveats) as part of "new" zcache; per cleancache performance
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+ feedback see https://lkml.org/lkml/2011/8/17/351, in
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+ staging/zcache for 3.9; dependent on proposed mm patch, see
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+ https://lkml.org/lkml/2012/1/25/300
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+5. DONE as part of "new" zcache; performance tuning only,
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+ in staging/zcache for 3.9; dependent on frontswap patch
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+ merged in 3.7 (33c2a174)
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+6. DONE (w/caveats), prototyped as part of "new" zcache, had
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+ bad memory leak; reimplemented to use sjennings clever tricks
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+ and proposed mm patches with new version in staging/zcache
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+ for 3.9, see https://lkml.org/lkml/2013/2/6/437;
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+7. PROTOTYPED as part of "new" zcache; in staging/zcache for 3.9;
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+ needs more review (plan to discuss at LSF/MM 2013)
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+8. IN PROGRESS; owned by Konrad Wilk; v2 recently posted
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+ http://lkml.org/lkml/2013/2/1/542
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+9. IN PROGRESS; owned by Konrad Wilk; Mel Gorman provided
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+ great feedback in August 2012 (unfortunately of "old"
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+ zcache)
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+10. Konrad posted series of fixes (that now need rebasing)
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+ https://lkml.org/lkml/2013/2/1/566
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+11. NOT DONE; owned by Konrad Wilk
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+12. TBD (depends on quantity of feedback)
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+13. PROPOSED; one suggestion proposed by Dan; needs more ideas/feedback
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+14. TBD (depends on feedback)
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+
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+WHO NEEDS TO AGREE
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+
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+Not sure. Seth Jennings is now pursuing a separate but semi-parallel
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+track. Akpm clearly has to approve for any mm merge to happen. Minchan
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+Kim has interest but may be happy if/when zram is merged into mm. Konrad
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+Wilk may be maintainer if akpm decides compression is maintainable
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+separately from the rest of mm. (More LSF/MM 2013 discussion.)
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+
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+ZCACHE FUTURE NEW FUNCTIONALITY
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+
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+A. Support zsmalloc as an alternative high-density allocator
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+ (See https://lkml.org/lkml/2013/1/23/511)
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+B. Support zero-filled pages more efficiently
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+C. Possibly support three zbuds per pageframe when space allows
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Dan Magenheimer