Provides control over the resources available to the shell and to processes started by it, on systems that allow such control.
Frequently used options
Report all current limits.
The maximum number of processes available to a single user.
The maximum number of file locks.
The maximum amount of memory available to the shell, in kilobytes.
Indicates that a hard limit is being specified.
Indicates that a soft limit is being specified.
View the current limits for a user:
ulimit -acore file size (blocks, -c) 0 data seg size (kbytes, -d) unlimited scheduling priority (-e) 0 file size (blocks, -f) unlimited pending signals (-i) 8192 max locked memory (kbytes, -l) 32 max memory size (kbytes, -m) unlimited 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) 10240 cpu time (seconds, -t) unlimited max user processes (-u) 8192 virtual memory (kbytes, -v) unlimited file locks (-x) unlimited
Limits are defined on Linux as being either hard or soft limits. A hard limit is set by the superuser for a user or group of users and cannot be exceeded. A soft limit is also set by the superuser, but it may be temporarily overridden by a user if the need arises (by the user calling the ulimit command). For example, a user may have a soft limit of 100 on the maximum number of open files, with a hard limit of 1,000. If the user is running ...