wlus and timings

[Finn-Arne Johansen <faj@bzz.no>]

Alot of our users have reported that it takes "forever" to add users to
the ldap using wlus and file import. Well, I guess there is good news
for the future. 

Using the sarge-based debian-edu image i build at random times, I've
tested some adding: 
- first I added 1 user to check that everything worked. (there has been
  some issues with samba in this image)
- Then I added 100 user from a file with the form 
   user0000;username00 full
   user0001;username00 full
   .
   user0099;username99 full
  This took about 1minute and 40 seconds
- Then i did the same with 400 users, which took about 12 minutes
  (yes andreas, i looked in my log)
- Then I tried to add 1000 users, which took about 40 minutes. but what
  I forgot, was that there is a sizelimit in the response from
  openldap, which by default is 500, but that we have set to 1000. i
  guess raising that value to 200 would have speeded up the process.
  The first 500 of the last thousand was significant faster than the
  last 500. 

All this was done with an old PIII, at some 800-900 MHz or something,
with the default kernel (2.4.27-1-386), and old scsis disks that came
with the machine. (80MB/s transfers) 

this is really a nice speedup from what we have in the woody-based
skolelinux/Debian-edu, where Ralf yesterday reported that he had
managed to add 80 users in 1 hour. 
Ralf: how many users did you have in advance ? Hav you tuned ldap to
give you more users when you query ? if not, change the sizelimit, sop
that it might give you all the users when you query. Also there is some
other parameters that you could tune in openldap, and also, remember to
edit nscd.conf on the clients. 

Another thing that we have noticed at Ulsrud, is that the NFS mounting
some times has problems. We have hard-coded changed the use of
netgroups in /etc/exports into dns-names, and since then we have not
had any problems, I think. basically what we did was change the line
that looked like this: 
 /skole/tjener/home0 @ltsp-server-hosts(rw) @workstation-hosts(rw) @server-hosts(rw)
into 
 /skole/tjener/home0 ltspserver*(rw) @workstation-hosts(rw) @server-hosts(rw)

On Ulsrud we are running Sarge-based ltsp-servers, and woody-based
mainserver. 
-- 
Finn-Arne Johansen 
faj@bzz.no
http://bzz.no/