Description of problem:

I ran the small-file performance test on NFS-Ganesh v4.0 mounted volume. After test, I observed performance drop in MKDIR and RMDIR FOPs by 18% and 15 %.  I executed this test on RHEL7.6 client. Please let me know you need more information on it.

Details : 
Our small file test does below things,
      1. Create 5000 on local as well as remote client (6 clients)
      2. Do Read, write, append, rename,delete-rename etc operation.

Step to Reproduce : 
     1. Configure 6 node cluster with replica-3 volume type
     2. Mount volume using 'NFS v4.0
     3. Start IO using small-file tool
     4. Calculate result. 

Gluster version : 
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[root@gqas001 ~]# rpm -qa | grep gluster
glusterfs-fuse-3.12.2-23.el7rhgs.x86_64
glusterfs-rdma-3.12.2-23.el7rhgs.x86_64
glusterfs-libs-3.12.2-23.el7rhgs.x86_64
glusterfs-3.12.2-23.el7rhgs.x86_64
glusterfs-cli-3.12.2-23.el7rhgs.x86_64
glusterfs-geo-replication-3.12.2-23.el7rhgs.x86_64
tmp-rhs-tests-beaker-rhs-gluster-qe-libs-dev-bturner-3.0-0.noarch
glusterfs-client-xlators-3.12.2-23.el7rhgs.x86_64
glusterfs-debuginfo-3.12.2-18.el7.x86_64
glusterfs-server-3.12.2-23.el7rhgs.x86_64
python2-gluster-3.12.2-23.el7rhgs.x86_64
glusterfs-api-3.12.2-23.el7rhgs.x86_64
[root@gqas001 ~]# 
###############
Options :
###############
performance.cache-samba-metadata: on
server.event-threads: 4
client.event-threads: 4
cluster.lookup-optimize: on
network.inode-lru-limit: 90000
performance.md-cache-timeout: 600
performance.cache-invalidation: on
performance.stat-prefetch: on
features.cache-invalidation-timeout: 600
features.cache-invalidation: on
transport.address-family: inet
nfs.disable: on
performance.client-io-threads: off
################
Volume Type : Replica-3
Cluster : 6 servers and 6 clients

FIPs: Disable : 

RHEL version : RHEL 7.6

Test Results : 
https://docs.google.com/spreadsheets/d/1B2obaj3w85O2xtzqc_anyJoDy9Nnejg3jvBl3mWivMc/edit#gid=0