features/shard: Performance improvements in IO path

         Backport of: http://review.gluster.org/#/c/12126/

This is patch 1/2 of the performance improvement work
for sharding in the IO path.
What this patch does:
Since the primary use-case where sharding is targeted -
VM store - is a single-writer workload, instead of
performing lookup on the base file everytime to gather the
size and block count from the backend in reads, writes and
truncate, now the size and block count is also cached and
kept up-to-date after every inode write in the inode ctx.

TO-DO:
Make changes in rename, link, unlink, [f]setattr and [f]stat
to keep the relevant iatt members up-to-date in the inode ctx.

Change-Id: Id4f5c33044411b87b55968083a70a0a11a335ab2
BUG: 1261716
Signed-off-by: Krutika Dhananjay <kdhananj@redhat.com>
Reviewed-on: http://review.gluster.org/12213
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Tested-by: NetBSD Build System <jenkins@build.gluster.org>
Reviewed-by: Pranith Kumar Karampuri <pkarampu@redhat.com>

0 files changed, 0 insertions, 0 deletions