Sysctl
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| − | '''sysctl''' is used to get/set various kernel and kernel module parameters | + | '''sysctl''' is used to get/set various kernel and kernel module parameters. |
| + | To get the value of a kernel parameter: | ||
| + | [root@splat ~]# '''sysctl hw.physmem''' | ||
| + | hw.physmem: 130453504 | ||
| + | |||
| + | To set the value of a kernel parameter: | ||
| + | |||
| + | [root@splat ~]# '''sysctl net.link.ether.bridge=0''' | ||
| + | net.link.ether.bridge: 1 -> 0 | ||
| + | |||
| + | Please note that some parameters are read-only and cannot be changed. | ||
| + | |||
| + | You can use the '''-a''' parameter to list all '''sysctl''' variables. Coupled with [[grep]] this makes a great way to find the '''sysctl''' variable you're looking for. | ||
| + | |||
| + | [root@splat ~]# '''sysctl -a | grep mem''' | ||
| + | vm.zone_kmem_pages: 182 | ||
| + | vm.zone_kmem_kvaspace: 14725120 | ||
| + | vfs.ufs.dirhash_maxmem: 2097152 | ||
| + | vfs.ufs.dirhash_mem: 292312 | ||
| + | hw.physmem: 130453504 | ||
| + | hw.usermem: 107544576 | ||
| + | |||
| + | Be careful when editing '''sysctl''' values. Invalid or incorrect settings could cause severe problems with your system. | ||
[[Category:System Commands]] | [[Category:System Commands]] | ||
Latest revision as of 11:55, 27 July 2005
sysctl is used to get/set various kernel and kernel module parameters.
To get the value of a kernel parameter:
[root@splat ~]# sysctl hw.physmem hw.physmem: 130453504
To set the value of a kernel parameter:
[root@splat ~]# sysctl net.link.ether.bridge=0 net.link.ether.bridge: 1 -> 0
Please note that some parameters are read-only and cannot be changed.
You can use the -a parameter to list all sysctl variables. Coupled with grep this makes a great way to find the sysctl variable you're looking for.
[root@splat ~]# sysctl -a | grep mem vm.zone_kmem_pages: 182 vm.zone_kmem_kvaspace: 14725120 vfs.ufs.dirhash_maxmem: 2097152 vfs.ufs.dirhash_mem: 292312 hw.physmem: 130453504 hw.usermem: 107544576
Be careful when editing sysctl values. Invalid or incorrect settings could cause severe problems with your system.
