[PATCH v2 0/7] Handle mmaped regions in cache

Atsushi Kumagai ats-kumagai at wm.jp.nec.com
Tue Mar 17 21:17:30 PDT 2015

Hello Petr,

>Because all pages must go into the cache, data is unnecessarily
>copied from mmapped regions to cache. Avoid this copying by storing
>the mmapped regions directly in the cache.
>First, the cache code needs a clean up clarification of the concept,
>especially the meaning of the pending list (allocated cache entries
>whose content is not yet valid).
>Second, the cache must be able to handle differently sized objects
>so that it can store individual pages as well as mmapped regions.
>Last, the cache eviction code must be extended to allow either
>reusing the read buffer or unmapping the region.
>  v3: do not mmap fractional pages
>  v2: add mmapped regions to page cache

Thanks for your re-posting.
I'm testing with the v3 patch, it works fine so far.
So v1.5.8 can be released next week.

Atsushi Kumagai

>Petr Tesarik (7):
>  cache: get rid of search loop in cache_add()
>  cache: allow to return a page to the pool
>  cache: do not allocate from the pending list
>  cache: add hit/miss statistics to the final report
>  cache: allocate buffers in one big chunk
>  cache: allow arbitrary size of cache entries
>  cache: store mapped regions directly in the cache
> cache.c        |  81 +++++++++++++++++----------------
> cache.h        |  16 +++++--
> makedumpfile.c | 138 ++++++++++++++++++++++++++++++++++-----------------------
> 3 files changed, 138 insertions(+), 97 deletions(-)

More information about the kexec mailing list