/PROC/SYS/FS Content Parsing

This subdirectory contains specific file system, file handle, Inode, dentry and quota information.

1,/proc/sys/fs/aio-max-nr

AIO-MAX-NR allows the maximum VALUE/PROC/SYS/FS/AIO-NR can grow to.

2,/proc/sys/fs/aio-nr

Aio-nr shows the current system-wide number of asynchronous IO requests.

3,/proc/sys/fs/bio_netoops

4,/proc/sys/fs/dentry-state

Tatus of the directory cache. Since directory entries is dynamically allocated and deallocated, this file indicates the current status. It holds six values of which only the first three is used:

• Nr_dentry-number of Dentries currently allocated
• Nr_unused-nuber of unused Dentries
• Age_limit-seconds after the entry was reclaimed, when memory was short

Last three values is not used and is always zero.

5,/proc/sys/fs/dir-notify-enable

This file controls dnotify, a directory notification mechanism, and would not be appear if dnotify support are compiled out. It is introduced with inotify in case some people want to disable dnotify support at runtime.

There is possible values:

• 1-dnotify is enabled (default)
• 0-dnotify is disabled

6,/proc/sys/fs/file-max

The kernel allocates file handles dynamically, but doesn ' t free them again at this time.

The value of File-max denotes the maximum number of file handles that the Linux kernel would allocate. When you get a lot of the error messages about running out of the file handles, you might want to raise this limit. The default value is 10% of RAM in kilobytes.

7,/proc/sys/fs/file-nr

Historically, the three values in FILE-NR denoted the number of allocated file handles, the number of allocated but unused File handles, and the maximum number of file handles. Linux 2.6 Always reports 0 as the number of free file handles-this are not a error, it just means that the number of all ocated file handles exactly matches the number of used file handles.

8,/proc/sys/fs/inode-nr

The file Inode-nr contains the first and the first and the from/proc/sys/fs/inode-state.

9,/proc/sys/fs/inode-state

Inode-state contains, actual numbers and five dummy values. The numbers are:

• Nr_inodes-denotes the number of inodes the system has allocated. This number is grow and shrink dynamically.
• Nr_free_inodes-represents the number of free inodes. Ie. The number of InUse inodes is (nr_inodes-nr_free_inodes).

10,/proc/sys/fs/lease-break-time

This file specifies the grace period (in seconds) the kernel grants to a process holding a file lease after it had SE NT a signal to that process notifying it, another process is waiting to open the file. If the lease holder does not remove or downgrade the lease within this grace period, the kernel forcibly breaks the lease.

11,/proc/sys/fs/leases-enable

This file can is used to enable or disable the file leases on a system-wide basis. If This file contains the value 0, leases is disabled. A Non-zero value enables leases.

12,/proc/sys/fs/nr_open

13,/proc/sys/fs/overflowgid

Some filesystems only support 16-bit Gids, although in Linux Gids is. When one of the these filesystems is mounted with writes enabled, the any GID that would exceed 65535 are translated to a fixed Val UE before being written to disk.

This sysctl allows the value of the fixed GID. The default is 65534.

14,/proc/sys/fs/overflowuid

Some filesystems only support 16-bit UIDs, although in Linux UIDs is. When one of the these filesystems is mounted with writes enabled, the any UID that would exceed 65535 are translated to a fixed Val UE before being written to disk.

This sysctl allows the value of the fixed UID. The default is 65534.

15,/proc/sys/fs/suid_dumpable

The value in this file determines whether core dump files is produced for Set-user-id or otherwise protected/tainted Bina Ries. Three different integer values can be specified:

• 0 (default)-This provides the traditional behaviour. A core dump is not being produced for a process which have changed credentials (by calling Seteuid (2), Setgid (2), or similar , or by executing a set-user-id or Set-group-id program) or whose binary does does have Read permission enabled.
• 1 ("Debug")-All processes dump core when possible. The core dump is owned by the file system user ID of the dumping process and no security is applied. This was intended for system debugging situations only. Ptrace is unchecked.
• 2 ("Suidsafe")-any binary which normally would not being dumped (see "0" above) was dumped readable by root only. This allows the user to remove the core dump file and not to read it. For security reasons core dumps in this mode would not be overwrite one another or other files. This mode was appropriate when administrators was attempting to debug problems in a normal environment.

16,/proc/sys/fs/inotify

The following interfaces can be used to limit the amount of kernel memory consumed by the INotify file system Event-monito Ring mechanism.

16.1/proc/sys/fs/inotify/max_queued_events

The value of this file was used when an application calls Inotify_init (2) to set a upper limit on the number of events tha T can is queued to the corresponding inotify instance. Events in excess of the this limit was dropped, but an In_q_overflow event was always generated.

16.2/proc/sys/fs/inotify/max_user_instances

16.3/proc/sys/fs/inotify/max_user_watches

/PROC/SYS/FS Content Parsing