09-19-2008
Just for emphasis, your results include the overhead of starting a large number of processes, and in each of them, printing a line of text to a buffered block device, and exiting the process. Bottlenecks in any of these operations are much more likely to explain the results than the thing you are trying to test.
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fuser(1M) fuser(1M)
NAME
fuser - list processes using a file or file structure
SYNOPSIS
file ... file ...] ...
DESCRIPTION
The command lists the process IDs of processes that have each specified file open. For block special devices, all processes using any file
on that device are listed. The process ID may be followed by a letter, identifying how the file is being used, as follows:
file is current directory of the process.
file is the root directory of the process, as set up by the command (see chroot(1M)).
The process has
file open.
The process has
file memory mapped.
file is the text file of the process.
The process IDs associated with each file are printed to standard output as a single line separated by spaces and terminated with a single
newline. All other output -- the file name, the letter, and the user name -- is written to standard error.
Options
has the following options:
Display the use of a mount point and any file beneath that
mount point. Each file must be a file system mount point.
Display the use of the named file only,
not the files beneath it if it is a mounted file system. This is the default.
Display the login user name in parentheses following each process ID.
Send the
signal to each process using each file. You must have appropriate privileges to kill processes that you do not own.
You can respecify options between groups of files. The new set of options replaces the old set. A dash by itself cancels all options cur-
rently in force.
Operands
has the following operand:
file One of the following values:
o With the option, the name of a file.
o With the option, the name of a mounted file system or special file.
o With the option, the name of a file system mount point.
NETWORKING FEATURES
You can use with NFS file systems or files. If the file name is in the format used in to identify an NFS file system, treats the NFS file
system as a block special device and identifies any process using that file system.
If contact with an NFS file system is lost, fails, since contact is required to obtain the file system identification. Once the NFS file
system is recontacted, stale file handles from the previous contact can be identified, provided that the NFS file system has the same file
system identification.
EXAMPLES
Terminate all processes that are preventing disk drive 1 from being unmounted, listing the process ID and login name of each process being
killed.
List process IDs and login names of processes that have the password file open.
Combine both the above examples into a single command line.
If the device is mounted on directory list the process IDs and login names of processes using the device. Alternately, if is the mount
point for an NFS file system, list process IDs and login names of processes using that NFS file system.
If is an NFS file system, list all processes using any file on that file system. If it is not an NFS file system, treat it as a regular
file.
SEE ALSO
ps(1), mount(1M), kill(2), signal(2).
STANDARDS CONFORMANCE
fuser(1M)