Timing for remote editing

[Booker bense]

I ran the following timing tests, first I did a query-replace in emacs
on the YMP( about 20 substitutions ) then used the ange-ftp package to
remotely edit the file doing the inverse of the query-replace. Y1 is 
the YMP, GRUMPY is the workstation (sparc).

 
dummy.f has about 100 lines

Y1[129]: time emacs dummy.f
0.7954u 0.5854s 1:33 1%

GRUMPY(85):time emacs /benseb at y1:dummy.f
2.5u 2.3s 2:50 2% 

time used by the ftp daemon on the YMP
benseb 61246   297        - null  0:00 [ ftpd ]


genden.f has about 600 lines

Y1[135]:time emacs genden.f
1.0475u 0.5304s 0:48 3%

GRUMPY(87): time emacs /benseb at y1:genden.f
3.6u 2.1s 1:44 5% 

time used by the ftp daemon on the YMP
benseb 65911   297 11:51:46 null  0:00 [ ftpd ]


In fact I had to get/save a 2500 line file before I used enough time
that ps would show a 1 second use by the ftpd. 

While these statistics will vary greatly depending on how many hops
the ftp has to make, I think they show a reasonable savings in YMP cpu
time. Average time to get/save a file using ange-ftp is about 3-5
seconds. The difference in user time between the YMP and the
workstation is largely due to the fact that I am using the X-windows
version of emacs and it takes a significant amount of time to load
emacs and open a new window, also I have to type in my password for the
ftp. What I like most about using the remote editor is that it allows
to keep the file in the editor without using any YMP time. Emacs, in
particular, can gobble a significant amount of time if you are doing 
complex operations. 

For an even more remote user, (my keypress has to go about 3 floors) I
think the improved interactivity of a distributed editor would be well
worth the extra time spent in startup. IMHO, 'AUTOMATED' distributed
editing, even for small files is a both user and cpu time efficent,
particularly on a system as heavily loaded as SDSC's. 

I would be very interested in seeing similar timings for an NFS'ed
file system on a YMP. In this case your editor doesn't need to get the
file but the compiler does.  i.e. 'time cf77 test.f' on a NFS'ed and a
non-NFS'ed file.

-Booker C. Bense /* benseb at grumpy.sdsc.edu */