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aarded
04-Feb-2015, 12:33
Hi,

We have 64 GB of memory, but when I ask "ulimit -a", it shows only 53GB. ulimit -aS gives the same values.

core file size (blocks, -c) 1
data seg size (kbytes, -d) unlimited
scheduling priority (-e) 0
file size (blocks, -f) unlimited
pending signals (-i) 515567
max locked memory (kbytes, -l) 64
max memory size (kbytes, -m) 56103908
open files (-n) 1024
pipe size (512 bytes, -p) 8
POSIX message queues (bytes, -q) 819200
real-time priority (-r) 0
stack size (kbytes, -s) 8192
cpu time (seconds, -t) unlimited
max user processes (-u) 515567
virtual memory (kbytes, -v) 66227600
file locks (-x) unlimited

How is it possible? What can be the cause of it? How can I ajust it?

tnx.

ab
04-Feb-2015, 12:40
ulimit doesn't show possible physical memory; you should use 'free' for that.

ulimit's purpose is to impose a limit on processes that need to use
memory. By definition (as I recall) it also does not apply to root-owned
processes, so a lot of server stuff, and of course the kernel does not
apply as it is above anything user-related (ring zero).

--
Good luck.

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jmozdzen
04-Feb-2015, 17:36
Hi aarded,

Hi,

We have 64 GB of memory, but when I ask "ulimit -a", it shows only 53GB. ulimit -aS gives the same values.

core file size (blocks, -c) 1
data seg size (kbytes, -d) unlimited
scheduling priority (-e) 0
file size (blocks, -f) unlimited
pending signals (-i) 515567
max locked memory (kbytes, -l) 64
max memory size (kbytes, -m) 56103908
open files (-n) 1024
pipe size (512 bytes, -p) 8
POSIX message queues (bytes, -q) 819200
real-time priority (-r) 0
stack size (kbytes, -s) 8192
cpu time (seconds, -t) unlimited
max user processes (-u) 515567
virtual memory (kbytes, -v) 66227600
file locks (-x) unlimited

How is it possible? What can be the cause of it? How can I ajust it?

tnx.

as "ab" already pointed out, "ulimit" shows the resource limits imposed on your environment by the admin (or system defaults). The given numbers don't have much to do with physical resources.

From "man bash":

ulimit [-SHacdefilmnpqrstuvx [limit]]
Provides control over the resources available to the shell and to processes started by it, on systems that allow such control.[...]

Have a look at /etc/security/limits.conf for current limits defined on your system.

Regards,
Jens