Improving NFS Performance Over Wireless Links. Rohit Dube, Cynthia D. Rais,and Satish K.Tripathi.Fellow,IEEE. 報告人 : 蔡昭明 學號 :492515265. Introduction (1). 1.Now:Mobile computing→The performance ◎currently limited by low bandwidth ◎high error rates ◎temporary disconnect
Rohit Dube, Cynthia D. Rais,and Satish K.Tripathi.Fellow,IEEE
◎high error rates
◎limited disk space
◎ fetch files from severs on the wired network via wireless links
◎ Limited wireless LAN networks
(bandwidths on the order of 1 Mbps ).
62%,which brings the performance to whithin 5% of that obtained in zero error conditions
◎ NFS uses block sizes
( From 8.192 to→1024bytes)
◎ Physiacl link→Maximum Transmission Unit (1500bytes)
1.Poor performance on the NFS client:
◎ Few losses will be retransmitted
(Add the timeout period)
◎ Exponentially increasing timeout values.
◎Use simpler mechanisms withmodifications only to the mobile NFS client and the wireless device drivers.
─Distribution with a good period mean of 1 sec.
─Distribution with a bad period means between 0 and 160 ms.
(1 MB files and 10 times)
─ A small block sizes increases in request and acknowledgment messages.
─ 4,096 bytes is the best on the testbed evironment .