OK, so I decide to really push the caching.  I activate the cache
(coda-cache 1) and copy a 7M image into a directory in
/coda/playground/thoth/.  the ls -l in another window shows the file
steadily growing in size.  At some point this shows up in the codacon:

Store b16.tif [7729] ( 14:06:58 )
Bandwidth jepthe.odyssey.cs.cmu.edu (12) --> 49130 B/s ( 14:07:03 )
Bandwidth jepthe.odyssey.cs.cmu.edu (6) --> 55268 B/s ( 14:07:13 )
Bandwidth jepthe.odyssey.cs.cmu.edu (13) --> 47645 B/s ( 14:07:18 )
Bandwidth jepthe.odyssey.cs.cmu.edu (9) --> 45964 B/s ( 14:07:23 )
Bandwidth jepthe.odyssey.cs.cmu.edu (8) --> 42313 B/s ( 14:07:28 )
BeginRvmFlush (1, 14116, T) ( 14:07:33 )
EndRvmFlush ( 14:07:33 )
Bandwidth jepthe.odyssey.cs.cmu.edu (14) --> 55944 B/s ( 14:07:33 )
Bandwidth jepthe.odyssey.cs.cmu.edu (11) --> 57628 B/s ( 14:07:40 )
Bandwidth jepthe.odyssey.cs.cmu.edu (13) --> 48385 B/s ( 14:07:45 )
Bandwidth jepthe.odyssey.cs.cmu.edu (15) --> 57231 B/s ( 14:07:50 )
Bandwidth jepthe.odyssey.cs.cmu.edu (17) --> 56963 B/s ( 14:07:55 )
Bandwidth jepthe.odyssey.cs.cmu.edu (15) --> 63430 B/s ( 14:08:00 )
BeginRvmFlush (1, 1284, T) ( 14:08:05 )
EndRvmFlush ( 14:08:05 )
Bandwidth jepthe.odyssey.cs.cmu.edu (16) --> 54992 B/s ( 14:08:05 )
Bandwidth jepthe.odyssey.cs.cmu.edu (18) --> 60594 B/s ( 14:08:10 )
Bandwidth jepthe.odyssey.cs.cmu.edu (10) --> 49223 B/s ( 14:08:15 )
Bandwidth jepthe.odyssey.cs.cmu.edu (10) --> 47852 B/s ( 14:08:20 )

  This is accompanied by messages in the venus.log talking about
"connection is strong" or "weak".  My guess is the threshold is 50KB/sec,
which happens to be about the speed of my connection :)

  I do another ls -l, and it's hung.  We'll see if it ever gets un-hung. 
The cp is still not complete.

  Slightly disappointing.  I consider it somewhat important that the
filesystem should keep working, even if some of the reads/writes block.

 frop:21 $ cat /proc/meminfo
        total:    used:    free:  shared: buffers:  cached:
Mem:  64765952 63868928   897024 39297024  3735552 24240128
Swap: 135761920        0 135761920


  I wonder if the following messages from dmesg are at all alarming:

Coda Kernel/User communications module 0.04
coda_read_super: rootfid is (-520093689, 1, 1)
coda_fetch_inode: inode called with i_ino = 0
coda_read_super: rootinode is 0 dev 5
coda_fetch_inode: inode called with i_ino = 0


  Well, now the ls is unhung and cp is complete.  At least it didn't
crash.  The whole episode took about 9 minutes I think.

-- 
Bob Forsman                                   thoth_at_gainesville.fl.us
           http://www.gainesville.fl.us/~thoth/