Re: Crontab question

"Robert M. Riches Jr." <spamtrap42@xxxxxxxxxxx> wrote:
On 2006-07-21, Floyd L. Davidson <floyd@xxxxxxxxxx> wrote:
"Robert M. Riches Jr." <spamtrap42@xxxxxxxxxxx> wrote:
On 2006-07-20, Floyd L. Davidson <floyd@xxxxxxxxxx> wrote:
"Robert M. Riches Jr." <spamtrap42@xxxxxxxxxxx> wrote:
...

If /home is mounted via NFS, there could be some delay
before another system would see changes.

Yeah, that should slow it down by perhaps what, 10 ms or so?

I don't remember specifics, but I have seen cases with /home
mounted via NFS among multiple systems that creation of a
new file or update of an existing file would suffer a delay
of many seconds before the creation or change would be
visible on another system. (It's warm enough this afternoon
I don't want to tax the air conditioner by booting up a
secondary system to run a test.)

That indicates an overloaded file server, not how fast an NFS
mounted file system is. It would be exactly the same delay for
file creation on the host that physically has the disk. For
reasonably loaded systems, with a reasonable network, far less
than the 10ms I indicated...

Of course you can mount filesystems NFS over dialup PPP link
too, and then of course there would be a significantly longer
delay. But even then, not "many seconds".

No overloading involved. There is simply a delay in caching
by NFS. If I remember the terminology correctly, it is
comparable to write-back vs. write-back memory caching.

I demonstrated that there is no such delay.

[the rest snipped]

Cite please.

--
Floyd L. Davidson <http://www.apaflo.com/floyd_davidson>
Ukpeagvik (Barrow, Alaska) floyd@xxxxxxxxxx
.

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