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Dell HPC NFS Storage Solution High Availability Configurations with Large Capacities
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A.10. Performance tuning on clients
1. If the clients access the NFS server via 10GbE, configure the MTU on the 10GbE device to be 8192
for all the clients. Note that the switches need to be configured to support large MTU as well.
On the client, if the value of MTU is not specified in /etc/sysconfig/network-
scripts/ifcfg-p2p1,
# echo “MTU=8192” >> /etc/sysconfig/network-scripts/ifcfg-p2p1,
Otherwise change the old value to 8192 in /etc/sysconfig/network-scripts/ifcfg-p2p1.
where ifcfg-p2p1 if the 10GbE network interface.
Restart the networking services.
# service network restart
2. If the clients access the NFS server via 10GbE, the Ethernet switches on the fabric should have flow
control disabled. The following instructions are for the PowerConnect 6248 and the PowerConnect
8024 and can be used as a reference.
Start a console session to the switch and type the following commands in sequence:
console>enable
console#configure
console(config)#no flowcontrol
In order to verify the setting of the option, type the following command:
console#show interface status
A message of “Flow Control:Disabled” will be printed out.
3. For each client, Add the following to /etc/sysctl.conf
Increasing the default TCP receive memory size
net.ipv4.tcp_rmem = 4096 2621440 16777216
Activate the changes with sysctl -p.