qlimit(1)
qlimit - show supported batch limits, and shell strategy for
the named host(s).
SYNOPSIS
qlimit [ -v ] [ host-name ... ]
DESCRIPTION
Qlimit displays the set of batch request resource limit
types that can be directly enforced on the implied local
host or named hosts, and also the batch request shell
strategy defined for the implied local host or named hosts.
If no host-names are given, then the information displayed
is only relevant to the local host. Otherwise, the
supported batch request limits, and batch request shell
strategy for each of the named hosts is displayed.
The -v switch indicates that the version of the program is
to be printed.
NQS supports many batch request resource limit types that
can be applied to an NQS batch request. However, not all
UNIX implementations are capable of supporting the rather
extensive set of limit types that NQS provides.
The set of limits applied to a batch request, is always
restricted to the set of limits that can be directly
supported by the underlying UNIX implementation. If a batch
request specifies a limit that cannot be enforced by the
underlying UNIX implementation, then the limit is simply
ignored, and the batch request will operate as though there
were no limit (other than the obvious physical maximums),
placed upon that resource type.
When an attempt is made to queue a batch request, each
limit-value specified by the request (that can also be
supported by the local UNIX implementation), is compared
against the corresponding limit-value as configured for the
destination batch queue. If the corresponding batch queue
limit-value for all batch request limit-values is defined as
unlimited, or is greater than or equal to the corresponding
batch request limit-value, then the request can be
successfully queued, provided that no other anomalous
conditions occur. For request infinity limit-values, the
corresponding queue limit-value must also be configured as
infinity.
These resource limit checks are performed irrespective of
the batch request arrival mechanism, either by a direct use
of the qsub(1) command, or by the indirect placement of a
batch request into a batch queue via a pipe queue. It is
queue if any of these resource limit checks fail.
Finally, if a request fails to specify a limit-value for a
resource limit type that is supported on the execution
machine, then the corresponding limit-value as configured
for the destination queue, becomes the limit-value for the
unspecified request limit.
Upon the successful queueing of a request in a batch queue,
the set of limits under which the request will execute is
frozen, and will not be modified by subsequent qmgr(1M)
commands that alter the limits of the containing batch
queue.
As mentioned above, this command also displays the shell
strategy as configured for the implied local host, or named
hosts. In the absence of a shell specification for a batch
request, NQS must choose which shell should be used to
execute that batch request. NQS supports three different
algorithms, or strategies to solve this problem that can be
configured for each system by a system administrator,
depending on the needs of the user's involved, and upon
system performance criterion.
The three possible shell strategies are called:
fixed,
free, and
login.
These shell strategies respectively cause the configured
fixed shell to be exec'd to interpret all batch requests,
cause the user's login shell as defined in the password file
to be exec'd which in turn chooses and spawns the
appropriate shell for running the batch shell script, or
cause only the user's login shell to be exec'd to interpret
the script.
A shell strategy of fixed means that the same shell as
chosen by the system administrator, will be used to execute
all batch requests.
A shell strategy of free will run the batch request script
exactly as would an interactive invocation of the script,
and is the default NQS shell strategy.
The strategies of fixed, and login exist for host systems
that are short on available free processes. In these two
strategies, a single shell is exec'd, and that same shell is
the shell that executes all of the commands in the batch
request shell script.
particular NQS system, then the "fixed" shell that will be
used to run all batch requests at that host is displayed.
SEE ALSO
qdel(1), qdev(1), qpr(1), qstat(1), and qsub(1) in the NPSN
UNIX System Programmer Reference Manual.
qmgr(1M) in the NPSN UNIX System Administrator Reference
Manual.
NPSN HISTORY
Origin: Sterling Software Incorporated
May 1986 - Brent Kingsbury, Sterling Software
Original release.
August, 1994 - John Roman, Monsanto Company
Version 3.36