[9fans] fun with cfs.

[9fans] fun with cfs.

[Ronald G. Minnich]

I've been playing around with lib9p and then started looking at cfs. You 
can do something with cfs that is kind of fun. 

I can send patches if anyone wants them. 

Basically, you rip all the caching out of cfs and you have a very nice 
tutorial program for seeing how 9p works. Took about 15 mins. You end up 
with cfs.c and (IIRC) stats.h or some such, so you get one .c file and you 
can then:
./cfs -S -d il!yourhost

And you get this nice mountpoint, which you can cd to, ls, to things in 
inside of .... all while watching the 9p traffic so you can see how it 
works. Good fun.

It would be great for showing people how 9p works or for classes. Even
better is letting poor suffering students do the same thing with nfs, and
then with 9p; you really start to appreciate 9p if you've done a lot of
NFS (which I have ...).

Now here's where somebody tells me: that file system already exists, just 
do x and y and z; so, if this is useless, well, I had fun anyway; if not, 
then I'll send the c-diffs as they are very short. 


thanks

ron

Re: [9fans] fun with cfs.

[Fco. J. Ballesteros]

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You have iostats and the -D flag in ramfs.
Isn't that what you want? Or am I sleeping?

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From: "Ronald G. Minnich" <rminnich@lanl.gov>
To: 9fans@cse.psu.edu
Subject: [9fans] fun with cfs.
Date: Wed, 12 Jan 2005 11:26:30 -0700 (MST)
Message-ID: <Pine.LNX.4.58.0501121117480.3521@bluesteel.lanl.gov>

I've been playing around with lib9p and then started looking at cfs. You 
can do something with cfs that is kind of fun. 

I can send patches if anyone wants them. 

Basically, you rip all the caching out of cfs and you have a very nice 
tutorial program for seeing how 9p works. Took about 15 mins. You end up 
with cfs.c and (IIRC) stats.h or some such, so you get one .c file and you 
can then:
./cfs -S -d il!yourhost

And you get this nice mountpoint, which you can cd to, ls, to things in 
inside of .... all while watching the 9p traffic so you can see how it 
works. Good fun.

It would be great for showing people how 9p works or for classes. Even
better is letting poor suffering students do the same thing with nfs, and
then with 9p; you really start to appreciate 9p if you've done a lot of
NFS (which I have ...).

Now here's where somebody tells me: that file system already exists, just 
do x and y and z; so, if this is useless, well, I had fun anyway; if not, 
then I'll send the c-diffs as they are very short. 


thanks

ron

Re: [9fans] fun with cfs.

[Ronald G. Minnich]

On Wed, 12 Jan 2005, Fco. J. Ballesteros wrote:

> You have iostats and the -D flag in ramfs.
> Isn't that what you want? Or am I sleeping?

the neat thing with cfs and my little hack is it serves 9p and you can
hook it to anything that serves 9p. So you can push it in front of any
9p server and watch what it does, which is kind of fun.

I'm actually beating on it for a totally different reason, I just did this 
little hack yesterday and realized I could use it to watch what any plan 9 
server is doing, which is kind of fun.

ron

Re: [9fans] fun with cfs.

[Russ Cox]

> Now here's where somebody tells me: that file system already exists, just
> do x and y and z; 

Well, you asked for it.

    iostats -df /fd/1 rc
    # play with anything

is one way.

    srvfs -d foo /
    tail -f /tmp/exportdb &
    mount /srv/foo /n/foo
    # play with /n/foo

is another.

Russ

Re: [9fans] fun with cfs.

[Ronald G. Minnich]

On Wed, 12 Jan 2005, Russ Cox wrote:

> > Now here's where somebody tells me: that file system already exists, just
> > do x and y and z; 
> 
> Well, you asked for it.

hmm, I knew I could count on you :-)

ron

Re: [9fans] fun with cfs.

[Ronald G. Minnich]

On Wed, 12 Jan 2005, Charles Forsyth wrote:

> >>    iostats -df /fd/1 rc
> >>   # play with anything
> 
> as it happens, `i knew that', but i wonder if little idioms like that
> might helpfully be added to the relevant manual pages in EXAMPLES.
> perhaps the more obscure ones could all be collected together in emacs(1).

yeah, I sure as heck did not know about iostats. I thought it showed 
iostats but never had enough sense to try it. It's quite neat. 

ron

Re: [9fans] fun with cfs.

[Charles Forsyth]

>>    iostats -df /fd/1 rc
>>   # play with anything

as it happens, `i knew that', but i wonder if little idioms like that
might helpfully be added to the relevant manual pages in EXAMPLES.
perhaps the more obscure ones could all be collected together in emacs(1).

Re: [9fans] fun with cfs.

[Russ Cox]

> > as it happens, `i knew that', but i wonder if little idioms like that
> > might helpfully be added to the relevant manual pages in EXAMPLES.
> > perhaps the more obscure ones could all be collected together in emacs(1).

done.
russ