readme

openPBS的开放源代码

#         OpenPBS (Portable Batch System) v2.3 Software License
# 
# Copyright (c) 1999-2000 Veridian Information Solutions, Inc.
# All rights reserved.
# 
# ---------------------------------------------------------------------------
# For a license to use or redistribute the OpenPBS software under conditions
# other than those described below, or to purchase support for this software,
# please contact Veridian Systems, PBS Products Department ("Licensor") at:
# 
#    www.OpenPBS.org  [phone]                  [e-mail]
#                        877 902-4PBS (US toll-free)
# ---------------------------------------------------------------------------
# 
# This license covers use of the OpenPBS v2.3 software (the "Software") at
# your site or location, and, for certain users, redistribution of the
# Software to other sites and locations.  Use and redistribution of
# OpenPBS v2.3 in source and binary forms, with or without modification,
# are permitted provided that all of the following conditions are met.
# After December 31, 2001, only conditions 3-6 must be met:
# 
# 1. Commercial and/or non-commercial use of the Software is permitted
#    provided a current software registration is on file at www.OpenPBS.org.
#    If use of this software contributes to a publication, product, or
#    service, proper attribution must be given; see www.OpenPBS.org/credit.html
# 
# 2. Redistribution in any form is only permitted for non-commercial,
#    non-profit purposes.  There can be no charge for the Software or any
#    software incorporating the Software.  Further, there can be no
#    expectation of revenue generated as a consequence of redistributing
#    the Software.
# 
# 3. Any Redistribution of source code must retain the above copyright notice
#    and the acknowledgment contained in paragraph 6, this list of conditions
#    and the disclaimer contained in paragraph 7.
# 
# 4. Any Redistribution in binary form must reproduce the above copyright
#    notice and the acknowledgment contained in paragraph 6, this list of
#    conditions and the disclaimer contained in paragraph 7 in the
#    documentation and/or other materials provided with the distribution.
# 
# 5. Redistributions in any form must be accompanied by information on how to
#    obtain complete source code for the OpenPBS software and any
#    modifications and/or additions to the OpenPBS software.  The source code
#    must either be included in the distribution or be available for no more
#    than the cost of distribution plus a nominal fee, and all modifications
#    and additions to the Software must be freely redistributable by any party
#    (including Licensor) without restriction.
# 
# 6. All advertising materials mentioning features or use of the Software must
#    display the following acknowledgment:
# 
#     "This product includes software developed by NASA Ames Research Center,
#     Lawrence Livermore National Laboratory, and Veridian Information
#     Solutions, Inc.
#     Visit www.OpenPBS.org for OpenPBS software support,
#     products, and information."
# 
# 7. DISCLAIMER OF WARRANTY
# 
# THIS SOFTWARE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. ANY EXPRESS
# OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
# OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT
# ARE EXPRESSLY DISCLAIMED.
# 
# IN NO EVENT SHALL VERIDIAN CORPORATION, ITS AFFILIATED COMPANIES, OR THE
# U.S. GOVERNMENT OR ANY OF ITS AGENCIES BE LIABLE FOR ANY DIRECT OR INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
# OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
# LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
# NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
# EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
# 
# This license will be governed by the laws of the Commonwealth of Virginia,
# without reference to its choice of law rules.
# Document Version 
# $Id: README,v 1.1.10.4 2000/08/09 00:19:11 hender Exp $

* The Configuration File

The scheduler's configuration file is a flat ASCII file.  Comments are
allowed anywhere, and begin with a '#' character.  Any non-comment lines
are considered to be statements, and must conform to the syntax :

	<option> <argument>

The descriptions of the options below describe the type of argument that
is expected for each of the options.  Arguments must be one of :

	<boolean>	A boolean value.  The strings "true", "yes", "on" and 
			"1" are all true, anything else evaluates to false.
	<hostname>	A hostname registered in the DNS system.
	<integer>	An integral (typically non-negative) decimal value.
	<pathname>	A valid pathname (i.e. "/usr/local/pbs/pbs_acctdir").
	<queue_spec>	The name of a PBS queue.  Either 'queue@exechost' or
			just 'queue'.  If the hostname is not specified, it
			defaults to the name of the local host machine.
	<real>		A real valued number (i.e. the number 0.80).
	<string>	An uninterpreted string passed to other programs.
	<time_spec>	A string of the form HH:MM:SS (i.e. 00:30:00 for
			thirty minutes, 4:00:00 for four hours).
	<variance>	Negative and positive deviation from a value.  The
			syntax is '-mm%,+nn%' (i.e. '-10%,+15%' for minus
			10 percent and plus 15% from some value).

Syntactical errors in the configuration file are caught by the parser, and
the offending line number and/or configuration option/argument is noted in
the scheduler logs.  The scheduler will not start while there are syntax
errors in its configuration files.

Before starting up, the scheduler attempts to find common errors in the
configuration files.  If it discovers a problem, it will note it in the
logs (possibly suggesting a fix) and exit.

The following is a complete list of the recognized options :

    AVOID_FRAGMENTATION				<boolean>
    BATCH_QUEUES				<queue_spec>[,<queue_spec>...]
    DECAY_FACTOR				<real>
    DEDICATED_QUEUE				<queue_spec>
    DEDICATED_TIME_CACHE_SECS			<integer>
    DEDICATED_TIME_COMMAND			<pathname>
    ENFORCE_ALLOCATION				<boolean>
    ENFORCE_DEDICATED_TIME			<boolean>
    ENFORCE_PRIME_TIME				<boolean>
    EXTERNAL_QUEUES				<queue_spec>[,<queue_spec>...]
    FAKE_MACHINE_MULT				<integer>
    HIGH_SYSTIME				<integer>
    INTERACTIVE_LONG_WAIT			<time_spec>
    MAX_DEDICATED_JOBS				<integer>
    MAX_JOBS					<integer>
    MAX_QUEUED_TIME				<time_spec>
    MAX_USER_RUN_JOBS				<integer>
    MIN_JOBS					<integer>
    NONPRIME_DRAIN_SYS				<boolean>
    OA_DECAY_FACTOR				<real>
    PRIME_TIME_END				<time_spec>
    PRIME_TIME_SMALL_NODE_LIMIT			<integer>
    PRIME_TIME_SMALL_WALLT_LIMIT		<time_spec>
    PRIME_TIME_START				<time_spec>
    PRIME_TIME_WALLT_LIMIT			<time_spec>
    SCHED_ACCT_DIR				<pathname>
    SCHED_HOST					<hostname>
    SCHED_RESTART_ACTION			<string>
    SERVER_HOST					<hostname>
    SMALL_JOB_MAX				<integer>
    SMALL_QUEUED_TIME				<time_spec>
    SORT_BY_PAST_USAGE				<boolean>
    SPECIAL_QUEUE				<queue_spec>
    SUBMIT_QUEUE				<queue_spec>
    SYSTEM_NAME					<hostname>
    TARGET_LOAD_PCT				<integer>
    TARGET_LOAD_VARIANCE			<variance>
    TEST_ONLY					<boolean>
    WALLT_LIMIT_LARGE_JOB			<time_spec>
    WALLT_LIMIT_SMALL_JOB			<time_spec>

These options are described in greater detail below.

* Overview Of Operation

This package contains the sources for a PBS scheduler (pbs_sched), which
was designed to be run on a cluster of Silicon Graphics, Inc. Origin2000
machines.  The function of the scheduler is to choose a job or jobs that
fit the resources and policy limits.  When a suitable job is found, the
scheduler will ask PBS to run that job on one of the execution hosts.  

Please be sure to read the section titled 'Configuring The Scheduler'
below before attempting to start the scheduler.

The basic mode of operation for the scheduler is this: 

 - Jobs are submitted to the PBS server by users.  The server enqueues
	them in the "default" queue (c.f. qmgr(1)). 

 - The scheduler wakes up and performs the following actions:

   + Get a list of jobs from the server.  Typically, the scheduler and
	server are run on the front-end, and only a resmom is needed on
	the execution hosts.  See the section on Scheduler Deployment.

   + Get available resource information from each execution host.  The
	resmom running on each host is queried for a set of resources
	for the host.  Scheduling decisions are made based upon these
	resources, queue limits, time of day, etc, etc.

   + Get information about the queues from the server.  The queues over
	which the scheduler has control are listed in the scheduler's
	configuration files.  The queues may be listed as batch, submit,
	external, special, or dedicated queues.  A job list is then
	created from the jobs on the submit, special and dedicated queues.

   + The list of jobs is sorted into a "preferred order" based upon the
	policy implementation (largest first during primetime, etc).
	This is the main mechanism by which policy such as "largest jobs
	first" and "maximize small job throughput" is implemented. 

   + For each job on the list of jobs, attempt to find a queue in which
	each job will fit.  Since the first job in the sorted list is the
	highest-priority job, the scheduler goes out of its way to ensure
	that it will be able to run it as soon as possible.

   + Since the submit queue resource limits must be large enough to hold
	any job that might run on any execution queue, it is possible for
	PBS to accept a submitted job that cannot fit on any queue.  These
	jobs are immediately rejected.

   + If a job fits on a queue and does not violate any policy requirements
	(like primetime walltime limits), ask PBS to move the job to that
	queue, and start it running.  If this succeeds, account for the
	expected resource drain and continue.  If the execution queue has
	a nodemask assigned to it (see the section on Nodemasks), the job
	is given a unique nodemask before being started.

   + If the job is not runnable at this time, the job comment will be
	modified to reflect the reason the job was not runnable (see the
	section on Lazy Comments).  Note that this reason may change from
	iteration to iteration, and that there may be several reasons that
	the job is not runnable now.

   + If any jobs are enqueued on the "external" queues, run as many as
	possible on the external queue.  This allows queues to be created
	and held idle unless jobs are enqueued upon them, in which case
	they are immediately started.

   + Clean up all allocated resources, and go back to sleep until the next
	round of scheduling is requested.

The scheduler attempts to pack the jobs into the queues as closely as
possible into the queues.  Queues are packed in a "first come, first
served" order.  There is an important detail to note here: each job is
scheduled individually, without a real lookahead scheme.

The PBS server will wake up the scheduler when jobs arrive or terminate,
so jobs should be scheduled immediately if the resources are (or become) 
available for them.  There is also a periodic run every few minutes,
although this is of dubious value. 

* Dedicated Time

    Related configuration options: