The performance of Native File Access for UNIX can be enhanced if you tune NSS performance.
For details on fine tuning NSS performance, refer to Fine Tuning NSS Performance in the Storage Services Administration Guide.
NFS Server has been tested with 300 clients simultaneously performing basic file operations using a script over NFS Version 2 and 3 with combinations using both UDP and TCP as transport. Over TCP the number of connections was scaled up to 600 using two IP addresses on the server and establishing two NFS connections per client.
Performance of NFS over TCP has improved almost five times over previous NFS releases and is now almost equivalent to UDP performance. Operations that used to take up to 25 minutes on an average, are now complete within 5 minutes.