maxfiles is very high

[Fernando Jose P de Souz]

My Server is a HP-UX 11.11 and is very Slow.

I Have an Ingress database. When i call the CA Support Analyst, he solicit to resize the maxfiles. The old value is 2048. The new value is 25000.
Is this value very high???

/oping2/ingres/files-ingres->ulimit -a
time(seconds) unlimited
file(blocks) unlimited
data(kbytes) 1048576
stack(kbytes) 8192
memory(kbytes) unlimited
coredump(blocks) 4194303
nofiles(descriptors) 25000

/oping2/ingres/files-ingres->ulimit -aH
time(seconds) unlimited
file(blocks) unlimited
data(kbytes) 1048576
stack(kbytes) 8192
memory(kbytes) unlimited
coredump(blocks) unlimited
nofiles(descriptors) 2048

Wait

[Bill Hassell]

25000 is not high if your system is using more than 15000 files at the same time. ulimit is just a set of local limitationsd and has nothing to do with the system-wide nfiles parameter. Use the command:

sar -v 1

to see how many files are currently open. Run this command several times during the day to see the highest value for nfile usage. If it is only 5000, then set nfiles to 8000 to give extra room when necessary.

[RAC_1]

maxfiles is the soft limit. This defines the max. files a process can open. (The hard limit is maxfiles_lim and nfile is system wide open files limit.)

Your value indeed looks a way too high. Instead of setting it to a number, use the formulae for maxfiles. Check /usr/conf/master.d/core-hpux file for formulae.

If you do not want to use a formulae, start by setting it aroung 4096. This depends on how may files a process opens. This should be fine.

Anil

[Chris Wilshaw]

We use Ingres on a number of systems. Depending on the number of iidbms/iislave processes that we're running, we use values of nfile from 6000 to 15000.

The setting of 15000 is used on an L3000 server with 2 iidbms processes, and 30 iislave processes). Under normal operation, 11000 of the available file slots are in use.

What model of server are you using, and what is your current ingres patch level (you can find this by looking in the /ingres_system/ingres/files/version.rel file).

[AISSAOUI Nourreddine]

Hi Fernando,

maxfiles defines the soft limit for the number of file descriptors per process while maxfiles_lim defines the hard limit.

You should always keep maxfiles < or = maxfiles_lim.

In you case if the value 25000 is justified, you should modify maxfiles_lim too.

maxfiles_lim = 25000 or better 30000 for example. It is better to keep maxfiles lower than maxfiles_lim.

nfiles needs to be greater than both of maxfiles and maxfiles_lim .

Is 25000 very high? Yes in general, but this will depend on the application. I personaly find it too high.

Did you ever seen the message "Too many open files"? If yes then you should increase maxfiles and maxfiles_lim.

[Tim Sanko]

I can say that you may not be high, but it depends how much application activity you have on your server and how much is database. Since you have ingres,

I suspect this is a DB server, and an application server. If it is also an application server that may be a reasonable parm. How many files are in your database for tables, etc. I am not asking the core, which is much higher. Add 20 files/user plus any unusual number for your application.

[Steven E. Protter]

Your system is probably slow not because so many files are open but because there is a large clump of files somewhere(other causes quite possible).

Lets say you have 10,000 files in one directory.

Then you do an ls or a find command in there.

That burns a lot of resources and can slow your response time system wide.

The answer is subdirectories. For other performance problems:

See my attached script set.

SEP