topic Re: How can you tell your current File-Max? in Operating System - Linux

How can you tell your current File-Max?

Jorge Cocomess — Thu, 24 Aug 2006 01:05:22 GMT

Hi,

How do you tell what's your file-max setting? I've been doing this;
ulimit -a user
And I look for open files
Is ulimit and file-max are the same thing?

The default value of open files is 1024. No matter what I tried, the new value doesn't stick and goes right back in the default value 1024.

Any ideas?

Thanks,
Jorge

Re: How can you tell your current File-Max?

Steven E. Protter — Thu, 24 Aug 2006 03:15:52 GMT

Shalom,

ulimit displays soft limits that can be changed in the user profile. Some products will object but you can go with unlimited if you wish.

There is also a hard limit in the kernel, which is stored in /proc virtual filesystems.

To avoid limitations, you should change both.

Summary: Not the same thing.

SEP

Re: How can you tell your current File-Max?

Atul Gautam — Thu, 24 Aug 2006 05:53:32 GMT

Hi Jorge,

If you are running linux, then the limits can be set in the file ---

/etc/security/limits.conf

and also you will have to use "pam_limits" module.

--
Atul

Re: How can you tell your current File-Max?

Atul Gautam — Thu, 24 Aug 2006 06:21:33 GMT

And yes Jorge......

as SEP has suggested...the values should not be the same..

Atul

Re: How can you tell your current File-Max?

Atul Gautam — Thu, 24 Aug 2006 06:22:01 GMT

And yes Jorge......

as SEP has suggested...the values should not be the same..

And the file /etc/security/limits.conf will itself provide with enough information.

--
Atul

Re: How can you tell your current File-Max?

Atul Gautam — Thu, 24 Aug 2006 06:23:49 GMT

And yes Jorge......

as SEP has suggested...the values should not be the same..

And the file /etc/security/limits.conf will itself provide you with enough information for setting up these options.

--
Atul

Re: How can you tell your current File-Max?

Jorge Cocomess — Thu, 24 Aug 2006 09:10:23 GMT

Hi,

I tried setting that up from the /etc/security/limits.conf -- After I made the changes to the limits.conf, I also manually made changes to the user, and here's the command that I used:
su - user
ulimit -n 65536 user

As soon as I exit and log back in and display the ulimit of that user, I still see the open files set at 1024.

The setting doesn't stick.

Where else should I look for?

Thanks,
J

Re: How can you tell your current File-Max?

Vitaly Karasik_1 — Thu, 24 Aug 2006 09:42:59 GMT

there are two different limits:

1) system-wide limits. You can see/set them under /proc or using sysctl (/etc/sysctl.conf) interface

2) user limits - "ulimit" and /etc/security/limits.conf.
Under limits.conf you can set soft and hard limits. Regular user can increase his limit up to his hard limit.

In RH linux, for example, default for max open files 1) limit is 1024 and for 2) is 50978.

You, probably, want to increase "per user" limit - so edit /etc/security/limits.conf and ask use to relogin - you'll see new value in "ulimit".

Rgds,
Vitaly

Re: How can you tell your current File-Max?

Bob_Vance — Fri, 25 Aug 2006 07:59:50 GMT

NOTE that you can set limits globally (user=*) and per user:

rac2node1 ## grep -e '^[^#]' /etc/security/limits.conf
... oracle soft nproc 4000
... oracle hard nproc 20000
... oracle soft nofile 4000
... oracle hard nofile 63000

When you log in, the settings are set to the soft limit first.

*Then*, you can bump the particular limit up (max= hard limit), which may be and usually is done in the .{bash}_profile.

NOTE that a NON-root user can only bump it *up* once, but that he can bump it down as often as desired.

::::

rac2node1 ## su - oracle

rac2node1 $$ ulimit -a
... ...
... open files (-n) 4000
... max user processes (-u) 4000

rac2node1 $$ ulimit -n 63001
... -bash: ulimit: open files: cannot modify limit: Operation not permitted

rac2node1 $$ ulimit -n 63000

rac2node1 $$ ulimit -n
... 63000
rac2node1 $ ulimit -n 8888
rac2node1 $$ ulimit -n
... open files (-n) 8888

rac2node1 $$ ulimit -n 9999
... -bash: ulimit: open files: cannot modify limit: Operation not permitted

rac2node1 $$ ulimit -n 7777

rac2node1 $$ ulimit -n 6666

rac2node1 $$ ulimit -n
... 6666

hth
bv