Path: utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!cs.utexas.edu!rice!sun-spots-request
From: per@erix.ericsson.se (Per Hedeland)
Newsgroups: comp.sys.sun
Subject: Re: mounted machine down => df hangs
Keywords: Networks
Message-ID: <3491@brazos.Rice.edu>
Date: 10 Dec 89 21:57:42 GMT
Sender: root@rice.edu
Organization: Sun-Spots
Lines: 31
Approved: Sun-Spots@rice.edu
X-Refs:  Original: v8n180, Replies: v8n188 v8n193 v8n194 v8n206
X-Sun-Spots-Digest: Volume 8, Issue 213, message 6 of 12

In article <2832@brazos.Rice.edu>, greg@sj.ate.slb.com (Greg Wageman) writes:
>This isn't a bug, it's a feature.
[lots of explanation deleted...]

Well, I'm sure most of us by now have a rather fixed opinion on the truth
of that statement, and I don't really intend to comment on it. However,
something occurred to me while discussing our latest manifestation of that
"feature" (mailtool hanging an entire SunView session because the "mail
server" had become inaccessible:-() - sorry if this has already been
discussed, if so I must have missed it:

As I see it, the purpose of hard mounts is to let programs that don't
handle errors on read/write/etc gracefully (which may in some cases be
hard to do), work "correctly" all the same. On the other hand, most of the
*problems* caused by hard mounts (such as these two examples) seem to be
at *initial* file access, i.e. open/stat/etc. (Or, put another way: Most
programs don't have files open for long periods of time.) Also, most
programs already handle errors at that point - e.g. they are prepared for
an expected file to be missing/ inaccessible etc.

Now, I know next to nothing about how the NFS protocol works, and thus how
feasible this would be, but my conclusion from the above is that it would
be *very* useful to have a soft_open_stat_etc_but_hard_read_write_etc
option when mounting NFS file systems. Anyone got any comments on this?
(Besides "Oh no, not *another* option!":-).

Regards
--Per Hedeland
per@erix.ericsson.se  or
per%erix.ericsson.se@uunet.uu.net  or
...uunet!erix.ericsson.se!per