Coda File System

Re: performance and disconnect?

From: Yui-wah LEE (Clement) <clement_at_ux3.sp.cs.cmu.edu>
Date: Tue, 21 Oct 1997 14:57:11 -0400 (EDT)
Bradley wrote:
> Hi,
> 
> I have coda running, and I was wondering if there are some magic
> incantations to improve performance.  I did a simple experiment
> running latex on a small file on my P5/90 laptop connected via modem:
> Case 1:  Local
>    cd /home/bradley
>    latex foo.tex
>   takes about 3 seconds
> 
> Case 2:  Remote
>    cd /coda/users/bradley
>    latex foo.tex
>   takes about 12 seconds
> Most of that 12 seconds apperas to be spent at the end when latex is
> trying to close the .dvi and .log and .aux files.
> 

When client is connected to the server (i.e. not in disconnected or
writedisconnect mode), client will ship the file back to server when
the file that has been written are closed (hence it will bring the
copy on server up to date).  That is probably the delay you see.  How
fast is your modem ?

> I tried doing
>  cfs disconnect
> but then nothing worked.  (Couldn't write anything)

Did you have two coda users on the client, and one of them (but not
you) was given the status of "primaryuser" ?  This is one of the
possible cause for this kind of problem.  When coda goes disconnected,
only one user own the client modification log (CML), which is where
all the local change recorded.

> Is there anything I can do to make my coda filesystem have performance
> more comparable to the local filesystem?
> 
> -Bradley
> 

There are currently some activities about write-back caching.  And
indeed there are still room of improvement in term of performance.  

-- Clement
Received on 1997-10-21 15:11:09