comments of FreeBSD(5.0) sysctls - BBS

kern.maxfilesperproc
Maximum files allowed open per process

kern.maxfiles
Maximum number of files

kern.openfiles
System-wide number of open files

kern.kq_calloutmax
Maximum number of callouts allocated for kqueue

kern.lastpid
Last used PID

security_jail.set_hostname_allowed
Processes in jail can set their hostnames

security_jail.socket_unixiproute_only
Processes in jail are limited to creating UNIX/IPv4/route sockets only

security_jail.sysvipc_allowed
Processes in jail can use System V IPC primitives

debug_ktr.alq_max
Maximum number of entries to write

debug_ktr.alq_cnt
Current number of written entries

debug_ktr.alq_failed
Number of times we overran the buffer

debug_ktr.alq_depth
Number of items in the write buffer

security_mac.enforce_fs
Enforce MAC policy on file system objects

security_mac.enforce_network
Enforce MAC policy on network packets

security_mac.enforce_pipe
Enforce MAC policy on pipe operations

security_mac.enforce_process
Enforce MAC policy on inter-process operations

security_mac.enforce_socket
Enforce MAC policy on socket operations

security_mac.enforce_vm
Enforce MAC policy on vm operations

security_mac.label_size
Pre-compiled MAC label size

security_mac.cache_fslabel_in_vnode
Cache mount fslabel in vnode

security_mac.vnode_label_cache_hits
Cache hits on vnode labels

security_mac.vnode_label_cache_misses
Cache misses on vnode labels

security_mac.mmap_revocation
Revoke mmap access to files on subject

security_mac.mmap_revocation_via_cow
Revoke mmap access to files via

security_mac_debug.label_fallback
Filesystems should fall back to fs label

kern.osrevision
Operating system revision

kern.osreldate
Operating system release date

kern.maxproc
Maximum number of processes

kern.maxprocperuid
Maximum processes allowed per userid

kern.maxusers
Hint for kernel tuning

kern.argmax
Maximum bytes of argument to execve(2)

kern.posix1version
Version of POSIX attempting to comply to

kern.ngroups
Maximum number of groups a user can belong to

kern.job_control
Whether job control is available

kern.saved_ids
Whether saved set-group/user ID is available

kern.saved_ids
Whether saved set-group/user ID is available

hw.ncpu
Number of active CPUs

hw.ncpu
Number of active CPUs

hw.byteorder
System byte order

hw.pagesize
System memory page size

regression.securelevel_nonmonotonic
securelevel may be lowered

user.bc_base_max
Max ibase/obase values in bc(1)

user.bc_dim_max
Max array size in bc(1)

user.bc_scale_max
Max scale value in bc(1)

user.bc_string_max
Max string length in bc(1)

user.coll_weights_max
Maximum number of weights assigned to an LC_COLLATE locale entry

user.line_max
Max length (bytes) of a text-processing utility's input line

user.re_dup_max
Maximum number of repeats of a regexp permitted

user.posix2_version
The version of POSIX 1003.2 with which the system attempts to comply

user.posix2_c_bind
Whether C development supports the C bindings option

user.posix2_c_dev
Whether system supports the C development utilities option

user.posix2_char_term


user.posix2_fort_dev
Whether system supports FORTRAN development utilities

user.posix2_fort_run
Whether system supports FORTRAN runtime utilities

user.posix2_localedef
Whether system supports creation of locales

user.posix2_sw_dev
Whether system supports software development utilities

user.posix2_upe
Whether system supports the user portability utilities

user.stream_max
Min Maximum number of streams a process may have open at one time

user.tzname_max
Min Maximum number of types supported for timezone names

debug_sizeof.vnode
sizeof(struct vnode)

debug_sizeof.proc
sizeof(struct proc)

debug_sizeof.cdev
sizeof(struct cdev)

debug_sizeof.bio
sizeof(struct bio)

debug_sizeof.buf
sizeof(struct buf)

debug_sizeof.kinfo_proc
sizeof(struct kinfo_proc)

debug_mutex_prof.enable
Enable tracing of mutex holdtime

debug_mutex_prof.acquisitions
Number of mutex acquistions recorded

debug_mutex_prof.records
Number of profiling records

debug_mutex_prof.maxrecords
Maximum number of profiling records

debug_mutex_prof.rejected
Number of rejected profiling records

debug_mutex_prof.hashsize
Hash size

debug_mutex_prof.collisions
Number of hash collisions

security_bsd.suser_enabled
processes with uid 0 have privilege

security_bsd.see_other_uids
Unprivileged processes may see subjects/objects with different real uid

security_bsd.unprivileged_proc_debug
Unprivileged processes may use process debugging facilities

kern.logsigexit
Log processes quitting on abnormal signals to syslog(3)

kern.sugid_coredump
Enable coredumping set user/group ID processes

kern.iov_max
Maximum number of elements in an I/O vector; sysconf(_SC_IOV_MAX)

kern_timecounter.tick

debug.bus_debug
Debug bus code

kern_devstat.numdevs
Number of devices in the devstat list

kern_devstat.version
Devstat list version number

debug_sizeof.disklabel
sizeof(struct disklabel)

debug_sizeof.diskslices
sizeof(struct diskslices)

debug_sizeof.disk
sizeof(struct disk)

kern_ipc.nmbclusters
Maximum number of mbuf clusters available

kern_ipc.nmbufs
Maximum number of mbufs available

kern_ipc.nmbcnt
Number used to scale kmem_map to ensure sufficient space for counters

kern_ipc.nsfbufs
Maximum number of sendfile(2) sf_bufs available

kern_ipc.mbuf_wait
Sleep time of mbuf subsystem wait allocations during exhaustion

kern.log_console_output


security_bsd.unprivileged_read_msgbuf
Unprivileged processes may read the kernel message buffer

debug.rman_debug
rman debug

kern_ipc.somaxconn
Maximum pending socket connection queue size

kern_ipc.numopensockets
Number of open sockets

kern_ipc_zero_copy.receive
Enable zero copy receive

kern_ipc_zero_copy.send
Enable zero copy send

kern_ipc.maxsockets
Maximum number of sockets avaliable

vfs_aio.num_queue_count
Number of queued aio requests

vfs_aio.num_buf_aio
Number of aio requests presently handled by the buf subsystem

vfs_aio.aiod_timeout
Timeout value for synchronous aio operations

vfs_aio.aiod_lifetime
Maximum lifetime for idle aiod

vfs_aio.unloadable
Allow unload of aio (not recommended)

vfs_aio.max_aio_per_proc
Maximum active aio requests per process (stored in the process)

vfs_aio.max_aio_queue_per_proc
Maximum queued aio requests per process (stored in the process)

vfs_aio.max_buf_aio
Maximum buf aio requests per process (stored in the process)

vfs.vmiodirenable
Use the VM system for directory writes

vfs.runningbufspace
Amount of presently outstanding async buffer io

vfs.bufspace
KVA memory used for bufs

vfs.maxbufspace
Maximum allowed value of bufspace (including buf_daemon)

vfs.bufmallocspace
Amount of malloced memory for buffers

vfs.maxmallocbufspace
Maximum amount of malloced memory for buffers

vfs.lobufspace
Minimum amount of buffers we want to have

vfs.hibufspace
Maximum allowed value of bufspace (excluding buf_daemon)

vfs.bufreusecnt
Number of times we have reused a buffer

vfs.buffreekvacnt
Number of times we have freed the KVA space from some buffer

vfs.bufdefragcnt
Number of times we have had to repeat buffer allocation to defragment

vfs.lorunningspace
Minimum preferred space used for in-progress I/O

vfs.hirunningspace
Maximum amount of space to use for in-progress I/O

vfs.numdirtybuffers
Number of buffers that are dirty (has unwritten changes) at the moment

vfs.lodirtybuffers
How many buffers we want to have free before bufdaemon can sleep

vfs.hidirtybuffers
When the number of dirty buffers is considered severe

vfs.numfreebuffers
Number of free buffers

vfs.lofreebuffers
XXX Unused

vfs.hifreebuffers
XXX Complicatedly unused

vfs.getnewbufcalls
Number of calls to getnewbuf

vfs.getnewbufrestarts
Number of times getnewbuf has had to restart a buffer aquisition

debug.dobkgrdwrite
Do background writes (honoring the BX_BKGRDWRITE flag)?

debug.disablecwd
Disable the getcwd syscall

debug.rcluster
Debug VFS clustering code

kern.maxvnodes
Maximum number of vnodes

kern.minvnodes
Minimum number of vnodes

debug.vnlru_nowhere
Number of times the vnlru process ran without success

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