Re: [veryRFC] [PATCH 0/2] reiser4: discard before dealloc: first approximation.

[Edward Shishkin <edward.shishkin@gmail.com>]

On 07/16/2014 01:24 PM, Ivan Shapovalov wrote:
> This needs your version of discard algorithm, because blocks inside extents of
> discard set are now marked as allocated.


OK, I'll try to finish it in weekends..


> BTW, have you dropped the case with erase unit size < block size?


In my version all erase units are supported except ones which are
not a power of 2. We can support all erase units without exceptions,
if needed.


>   This is
> probably OK, but configurations with nonzero alignments are then broken.


I support alignments with (bdev_discard_alignment % sb->s_blocksize == 0)
We can support all alignments without exceptions, but it will lead to 
complications
in discard_sorted_extents().


>   Not
> worth handling these, I think, but nevertheless a warning could be useful ;)

Agreed. It is important.

Thanks!
Edward.


>
> Ivan Shapovalov (2):
>    reiser4: discard support: perform discards and deallocations after writing logs.
>    reiser4: discard support: proof-of-concept for "discard before dealloc".
>
>   fs/reiser4/block_alloc.c | 48 +++++++++++++++++++-------------------
>   fs/reiser4/discard.c     | 60 ++++++++++++++++++++++++++++++++++--------------
>   fs/reiser4/discard.h     |  4 +++-
>   fs/reiser4/txnmgr.c      | 35 ----------------------------
>   fs/reiser4/txnmgr.h      | 13 ++---------
>   fs/reiser4/wander.c      |  3 ++-
>   6 files changed, 73 insertions(+), 90 deletions(-)
>