Path: utzoo!utgpu!water!watmath!clyde!bellcore!decvax!ucbvax!hplabs!hpda!hpesoc1!hpindda!uppal
From: uppal@hpindda.HP.COM (Sanjay Uppal)
Newsgroups: comp.unix.wizards
Subject: Re: NFS performance: a question
Message-ID: <4470001@hpindda.HP.COM>
Date: 11 Feb 88 00:36:45 GMT
References: <663@noao.UUCP>
Organization: HP Information Networks, Cupertino, CA
Lines: 17

As has been mentioned before, the asynchronous option would
go against the stateless nature of NFS if one wanted to 
recover from crashes correctly. However, I believe that
for the latest revision of the protocol SUN will allow
such a call to be made.

In UNIX, for files greater than the number of directly accessed
blocks, the indirect block too has to be written to the disk
synchronously. That makes it 3 blocks to be written synchronously
for every data block. Not only does this decrease the overlapped
processing with the cpu, but also increases the average time
to write a block as the blocks are no longer physically sequential.


Sanjay Uppal (NN9T, VU2SMT)	phone:	(408) 447-3864
Hewlett-Packard (IND)		uucp: ...!hplabs!hpda!uppal
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