topic Re: NUM_CLIENTS in Operating System - HP-UX

NUM_CLIENTS

Greg Conn — Wed, 06 Jun 2001 16:01:15 GMT

I have an application I am installing on HPUX 10.20. It wants me to make some kernel changes. It is asking for
NFLOCK (200+(10*NUM_CLIENTS)) 1024.

What is NUM_CLIENTS? The reason I am asking is because it is wrong now but the formula is right so the only thing that could be wrong is NUM_CLIENTS.
Thanks in advance!

Re: NUM_CLIENTS

A. Clay Stephenson — Wed, 06 Jun 2001 16:46:39 GMT

Hi Greg,

That is really a pseedo params and is your best guess as to the number of diskless workstations that use this server as an NFS server. It probably makes more sense to clobber the formula and replace it with a value that represents your best guess of the number of file locks you will need at one time.

Clay

Re: NUM_CLIENTS

Tony Escujuri — Wed, 06 Jun 2001 17:02:07 GMT

Greg,

You can find this tunable Kernel parameter in /stand/system.

After you make the change to the system file do the following:
/usr/sbin/mk_kernel -s ./system

Backup the vmunix and system files. to *.old and then if the system doesn't boot from the new kernel use the old one.
mv the /stand/build/system to ..
and mv the /stand/build/system to ..

Good Luck,
Tony Escujuri tony@unixadm.net

Re: NUM_CLIENTS

Tony Escujuri — Wed, 06 Jun 2001 17:09:16 GMT

Greg here is the complete steps to take to change this parameter:
cd /stand/build

/usr/lbin/sysadm/system_prep -s system

vi system file and make neccessary changes to it.

/usr/sbin/mk_kernel -s ./system

mv /stand/system /stand/system.old
mv /stand/vmunix /stand/vmunix.old

cp /stand/build/system /stand
cp /stand/build/vmunix_test /stand/vmunix

shutdown -r -y 0

use sysdef and ioscan to check out the changes to the parameters.

Tony Escujuri
tony@unixadm.net

Re: NUM_CLIENTS

Steffi Jones_1 — Wed, 06 Jun 2001 18:05:26 GMT

Hi Greg,

here is what I have saved at one time about num_clients:

What is the "num_clients" kernel parameter and what are reasonable values for it?
*********************************************************************************

The "num_clients" kernel parameter is used to parameterize other tunables
whose values need to be adjusted based on the number of clients in
a cluster (e.g., nflocks).
The value of "num_clients" does not have to exactly match the number
of clients in the cluster, it just needs to be greater than the number of
installed clients minus 10 (for example, if there are 30
installed clients, the value of "num_clients" should equal 20 or more),
and can safely be larger without constraint (within reason--
setting "num_clients" to 100 when there will only be 10 installed
clients is wasteful of server memory, but setting it to 50 when
there are only 30 installed clients is reasonable).
When SAM is used to add clients to a cluster, it will check the
current setting of "num_clients" and compare it to the new number
of installed clients. If the value of "num_clients" is greater than
the number of installed clients, this is OK. If the number of installed
clients is greater than the value of "num_clients," but not by more
than 10 clients, SAM will generate an informational message to the
effect that "num_clients" is OK, though less than the current number
of installed clients, and if the cluster is going to become larger
it may be necessary to increase the value of "num_clients." If the
number of installed clients exceeds the value of "num_clients" by
more than 10, SAM generates a more strongly worded message, telling
the user that the value of this parameter needs to be increased
before booting the new clients.
In the latter two cases above, SAM provides the option to enter
a new value for "num_clients." If a new value is specified,
SAM will update the server's kernel and reboot the server.

Steffi Jones

Re: NUM_CLIENTS

Greg Conn — Wed, 06 Jun 2001 18:10:57 GMT

Thanks Steffi. You talk about SAM leting you change it when there is an error. Is there a way to change it when I want? I tried Tony's way but it seems geared more towards 11.0. It did not work. I see the value in /stand/system but it did not chnage when I tried.

Re: NUM_CLIENTS

Steffi Jones_1 — Wed, 06 Jun 2001 18:27:09 GMT

Hi Greg,

I checked one of our 10.20 boxes and the easiest way would be to go into sam and change it there.

Steffi Jones