[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

Re: [K12OSN] Just about ready to make a purchase



On Tue, 08 May 2007 15:26:02 -0500, Les Mikesell wrote
> Jim Kronebusch wrote:
> 
> > I had looked at using SMB/LDAP along with multiple less powerful load balanced LTSP
> > servers, but from my testing the NFS shared /home and the remote users in LDAP had a
> > significant effect in speeds.  Machine bootup and general navigation seemed delayed. 
> > This is why I am looking at keeping storage and user accounts local on a single server.
> 
> This doesn't make a lot of sense.  There shouldn't be much traffic to 
> /home during bootup.  Are you sure you didn't create a network 
> bottleneck with server location?  I'd expect several dual-nic servers 
> with isolated client networks to be faster.

My tests have been with all servers on a single GB switch.  I had a separate SMB/LDAP
server which had a 1.5Ghz processor and 1GB of RAM running from a single IDE internally
and a single GB NIC plugged into a 8 port GB switch.  The test LTSP server was K12LTSP
v6 with a Dual 1Ghz Xeons and 1GB RAM running from a mirrored SCSI array locally
(running the OS) and single GB NIC connected to the same 8 port GB switch.  The /home
server is our current file server running Dual 3Ghz Xeon's and 4GB RAM running the os
from a internal PERC connected to a PowerVault with 2 36GB SCSI's mirrored, /home on
this server is running from 4 300GB SCSI drives in a RAID 5 in the same PowerVault, the
file server has dual GB NIC's with ALB and was connected to the same 8 port GB switch.

When I would power on a single client (Diskless Workstations Term 150) it would take a
little over a minute to power on (around 35 seconds standalone).  Once booted menus had
a 1-2 second lag and applications took 4-5 seconds longer to open and close.  If I use
local users and only NFS mount /home The lag is down to about .5 seconds from a
standalone.  If I get user info from LDAP and used a local /home the lag was also about
.5 seconds from standalone.  If I used a local /home and a local user base things went
as fast as a new local workstation.  This made me very nervous to go with a NFS /home
and LDAP for users for many clients.  When I booted 20 clients to test, the lag did not
seem to increase at all in any configuration, but that initial difference was enough to
make the system seem (in my opinion) substandard.  I want this implementation to seem
FAST.  If we had already been using this for years the small lag would have probably
seemed insignificant.  But I don't want to risk a perception of being slow.  I know the
test servers are less than desirable for a large scale implementation, but for the small
test environment this did not seem acceptable.

This did not seem normal to me as many users are using SMB/LDAP with NFS mounted /homes
and have not complained at all about speed.  But maybe that slight 1-2 second lag is
insignificant to others.  I would like to have a separate LDAP server for other purposes
as well, so I'll accept any suggestions as to how to increase its speed.  

Thanks Les.

-- 
This message has been scanned for viruses and
dangerous content by the Cotter Technology 
Department, and is believed to be clean.


[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]