[Gluster-devel] Eager-lock with more than 1 open-fds

[Pranith Kumar Karampuri]

hi,
     To improve performance, I posted the first cut of patches at the following 
URLs:

http://review.gluster.org/5238
http://review.gluster.org/5239
http://review.gluster.com/3904

I only did the base case test of 50 processes writing to a file in parallel 
which is working fine :-),
Without this patch latency as per profile info used to be:
 %-latency   Avg-latency   Min-Latency   Max-Latency   No. of calls         Fop
 ---------   -----------   -----------   -----------   ------------        ----
     99.86  632698.45 us      17.00 us 1999724.00 us            126    FINODELK

With this patch:
     29.07      23.28 us      10.00 us    1826.00 us        1149786    FINODELK
 
still need to test these patches thoroughly. Sending this mail to gather early 
review comments.

    This implementation gets open-fd-count on a file for lookup and 
data/metadata transactions to begin with. If the open-fd-count
is greater than 1 then eager-lock is turned off for the transactions. I am 
planning to add
similar logic for open, fsync, flush. Getting open-fd-counts in inode-read fops 
may not be a good idea in
my opinion because those fops don't have cluster view. Please let me know your 
views.

Pranith