NFS Services Administrator's Guide (B.11.31.03) August 2008

nfsstat -rc
2. If the timeout and retrans values displayed by nfsstat -rc are high, but
the badxid value is close to zero, packets are being dropped before they get to
the NFS server.
Try decreasing the values of the wsize and rsize mount options to 4096 or 2048
on the NFS clients. See “Changing the Default Mount Options” (page 55)“Changing
the Default Mount Options” on page 51 .
See Installing and Administering LAN/9000 Software for information on
troubleshooting LAN problems.
3. If the timeout and badxid values displayed by nfsstat -rc are of the same
magnitude, your server is probably slow. Client RPC requests are timing out and
being retransmitted before the NFS server has a chance to respond to them.
Try doubling the value of the timeo mount option on the NFS clients. See
“Changing the Default Mount Options” (page 55)“Changing the Default Mount
Options” on page 51.
Improve NFS Server Performance
□ Enter the following command to check your server’s memory utilization:
netstat -m
If the number of requests for memory denied is high, your server does not
have enough memory, and NFS clients will experience poor performance. Consider
adding more memory or using a different host as the NFS server.
□ Put heavily used directories on different disks on your NFS servers so they can be
accessed in parallel.
□ Enter the following command on the NFS server:
vmstat -n
If the us and sy values under cpu are high, and the id (idle time) value under
cpu is close to zero, your server’s CPU is heavily loaded. Try using a faster machine
as your NFS server. Do not use a gateway or a terminal server as an NFS or NIS
server.
□ Enter the following command to determine which processes are using the most
CPU:
/usr/bin/top
The top program sorts the processes running on your system, with the most
CPU-intensive process at the top of the display. It refreshes the display every five
seconds. Try taking some CPU-intensive processes off the server.
Type q to exit the top program.
□ Log into the NFS server and enter the following command:
138 Troubleshooting NFS Services