NAME
sched_conf - Sun Grid Engine default scheduler configuration file
DESCRIPTION
sched_conf defines the configuration file format for Sun Grid Engine's
scheduler. In order to modify the configuration, use the graphical
user's interface qmon(1) or the -msconf option of the qconf(1) command.
A default configuration is provided together with the Sun Grid Engine
distribution package.
Note, Sun Grid Engine allows backslashes (\) be used to escape newline
(\newline) characters. The backslash and the newline are replaced with
a space (" ") character before any interpretation.
FORMAT
The following parameters are recognized by the Sun Grid Engine
scheduler if present in sched_conf:
algorithm
Note: Deprecated, may be removed in future release.
Allows for the selection of alternative scheduling algorithms.
Currently default is the only allowed setting.
load_formula
A simple algebraic expression used to derive a single weighted load
value from all or part of the load parameters reported by sge_execd(8)
for each host and from all or part of the consumable resources (see
complex(5)) being maintained for each host. The load formula
expression syntax is that of a summation weighted load values, that is:
{w1|load_val1[*w1]}[{+|-}{w2|load_val2[*w2]}[{+|-}...]]
Note, no blanks are allowed in the load formula.
The load values and consumable resources (load_val1, ...) are
specified by the name defined in the complex (see complex(5)).
Note: Administrator defined load values (see the load_sensor parameter
in sge_conf(5) for details) and consumable resources available for all
hosts (see complex(5)) may be used as well as Sun Grid Engine default
load parameters.
The weighting factors (w1, ...) are positive integers. After the
expression is evaluated for each host the results are assigned to the
hosts and are used to sort the hosts corresponding to the weighted
load. The sorted host list is used to sort queues subsequently.
The default load formula is "np_load_avg".
job_load_adjustments
The load, which is imposed by the Sun Grid Engine jobs running on a
system varies in time, and often, e.g. for the CPU load, requires some
amount of time to be reported in the appropriate quantity by the
operating system. Consequently, if a job was started very recently, the
reported load may not provide a sufficient representation of the load
which is already imposed on that host by the job. The reported load
will adapt to the real load over time, but the period of time, in which
the reported load is too low, may already lead to an oversubscription
of that host. Sun Grid Engine allows the administrator to specify
job_load_adjustments which are used in the Sun Grid Engine scheduler to
compensate for this problem.
The job_load_adjustments are specified as a comma separated list of
arbitrary load parameters or consumable resources and (separated by an
equal sign) an associated load correction value. Whenever a job is
dispatched to a host by the scheduler, the load parameter and
consumable value set of that host is increased by the values provided
in the job_load_adjustments list. These correction values are decayed
linearly over time until after load_adjustment_decay_time from the
start the corrections reach the value 0. If the job_load_adjustments
list is assigned the special denominator NONE, no load corrections are
performed.
The adjusted load and consumable values are used to compute the
combined and weighted load of the hosts with the load_formula (see
above) and to compare the load and consumable values against the load
threshold lists defined in the queue configurations (see
queue_conf(5)). If the load_formula consists simply of the default CPU
load average parameter np_load_avg, and if the jobs are very compute
intensive, one might want to set the job_load_adjustments list to
np_load_avg=1.00, which means that every new job dispatched to a host
will require 100 % CPU time, and thus the machine's load is instantly
increased by 1.00.
load_adjustment_decay_time
The load corrections in the "job_load_adjustments" list above are
decayed linearly over time from the point of the job start, where the
corresponding load or consumable parameter is raised by the full
correction value, until after a time period of
"load_adjustment_decay_time", where the correction becomes 0. Proper
values for "load_adjustment_decay_time" greatly depend upon the load or
consumable parameters used and the specific operating system(s).
Therefore, they can only be determined on-site and experimentally. For
the default np_load_avg load parameter a "load_adjustment_decay_time"
of 7 minutes has proven to yield reasonable results.
maxujobs
The maximum number of jobs any user may have running in a Sun Grid
Engine cluster at the same time. If set to 0 (default) the users may
run an arbitrary number of jobs.
schedule_interval
At the time the scheduler thread initially registers at the event
master thread in sge_qmaster(8)process schedule_interval is used to set
the time interval in which the event master thread sends scheduling
event updates to the scheduler thread. A scheduling event is a status
change that has occurred within sge_qmaster(8) which may trigger or
affect scheduler decisions (e.g. a job has finished and thus the
allocated resources are available again).
In the Sun Grid Engine default scheduler the arrival of a scheduling
event report triggers a scheduler run. The scheduler waits for event
reports otherwise.
Schedule_interval is a time value (see queue_conf(5) for a definition
of the syntax of time values).
queue_sort_method
This parameter determines in which order several criteria are taken
into account to product a sorted queue list. Currently, two settings
are valid: seqno and load. However in both cases, Sun Grid Engine
attempts to maximize the number of soft requests (see qsub(1) -s
option) being fulfilled by the queues for a particular as the primary
criterion.
Then, if the queue_sort_method parameter is set to seqno, Sun Grid
Engine will use the seq_no parameter as configured in the current queue
configurations (see queue_conf(5)) as the next criterion to sort the
queue list. The load_formula (see above) has only a meaning if two
queues have equal sequence numbers. If queue_sort_method is set to
load the load according the load_formula is the criterion after
maximizing a job's soft requests and the sequence number is only used
if two hosts have the same load. The sequence number sorting is most
useful if you want to define a fixed order in which queues are to be
filled (e.g. the cheapest resource first).
The default for this parameter is load.
halftime
When executing under a share based policy, the scheduler "ages" (i.e.
decreases) usage to implement a sliding window for achieving the share
entitlements as defined by the share tree. The halftime defines the
time interval in which accumulated usage will have been decayed to half
its original value. Valid values are specified in hours or according to
the time format as specified in queue_conf(5).
If the value is set to 0, the usage is not decayed.
usage_weight_list
Sun Grid Engine accounts for the consumption of the resources CPU-time,
memory and IO to determine the usage which is imposed on a system by a
job. A single usage value is computed from these three input parameters
by multiplying the individual values by weights and adding them up. The
weights are defined in the usage_weight_list. The format of the list is
cpu=wcpu,mem=wmem,io=wio
where wcpu, wmem and wio are the configurable weights. The weights are
real number. The sum of all tree weights should be 1.
compensation_factor
Determines how fast Sun Grid Engine should compensate for past usage
below of above the share entitlement defined in the share tree.
Recommended values are between 2 and 10, where 10 means faster
compensation.
weight_user
The relative importance of the user shares in the functional policy.
Values are of type real.
weight_project
The relative importance of the project shares in the functional policy.
Values are of type real.
weight_department
The relative importance of the department shares in the functional
policy. Values are of type real.
weight_job
The relative importance of the job shares in the functional policy.
Values are of type real.
weight_tickets_functional
The maximum number of functional tickets available for distribution by
Sun Grid Engine. Determines the relative importance of the functional
policy. See under sge_priority(5) for an overview on job priorities.
weight_tickets_share
The maximum number of share based tickets available for distribution by
Sun Grid Engine. Determines the relative importance of the share tree
policy. See under sge_priority(5) for an overview on job priorities.
weight_deadline
The weight applied on the remaining time until a jobs latest start
time. Determines the relative importance of the deadline. See under
sge_priority(5) for an overview on job priorities.
weight_waiting_time
The weight applied on the jobs waiting time since submission.
Determines the relative importance of the waiting time. See under
sge_priority(5) for an overview on job priorities.
weight_urgency
The weight applied on jobs normalized urgency when determining priority
finally used. Determines the relative importance of urgency. See
under sge_priority(5) for an overview on job priorities.
weight_priority
The weight applied on jobs normalized POSIX priority when determining
priority finally used. Determines the relative importance of POSIX
priority. See under sge_priority(5) for an overview on job priorities.
weight_ticket
The weight applied on normalized ticket amount when determining
priority finally used. Determines the relative importance of the
ticket policies. See under sge_priority(5) for an overview on job
priorities.
flush_finish_sec
The parameters are provided for tuning the system's scheduling
behavior. By default, a scheduler run is triggered in the scheduler
interval. When this parameter is set to 1 or larger, the scheduler will
be triggered x seconds after a job has finished. Setting this parameter
to 0 disables the flush after a job has finished.
flush_submit_sec
The parameters are provided for tuning the system's scheduling
behavior. By default, a scheduler run is triggered in the scheduler
interval. When this parameter is set to 1 or larger, the scheduler
will be triggered x seconds after a job was submitted to the system.
Setting this parameter to 0 disables the flush after a job was
submitted.
schedd_job_info
The default scheduler can keep track why jobs could not be scheduled
during the last scheduler run. This parameter enables or disables the
observation. The value true enables the monitoring false turns it off.
It is also possible to activate the observation only for certain jobs.
This will be done if the parameter is set to job_list followed by a
comma separated list of job ids.
The user can obtain the collected information with the command qstat
-j.
params
This is foreseen for passing additional parameters to the Sun Grid
Engine scheduler. The following values are recognized:
DURATION_OFFSET
If set, overrides the default of value 60 seconds. This
parameter is used by the Sun Grid Engine scheduler when planning
resource utilization as the delta between net job runtimes and
total time until resources become available again. Net job
runtime as specified with -l h_rt=... or -l s_rt=... or
default_duration always differs from total job runtime due to
delays before and after actual job start and finish. Among the
delays before job start is the time until the end of a
schedule_interval, the time it takes to deliver a job to
sge_execd(8) and the delays caused by prolog in queue_conf(5) ,
start_proc_args in sge_pe(5) and starter_method in queue_conf(5)
. The delays after job finish include delays due to a forced job
termination (notify, terminate_method or checkpointing),
procedures run after actual job finish, such as stop_proc_args
in sge_pe(5) or epilog in queue_conf(5) , and the delay until a
new schedule_interval.
If the offset is too low, resource reservations (see
max_reservation) can be delayed repeatedly due to an overly
optimistic job circulation time.
JC_FILTER
Note: Deprecated, may be removed in future release.
If set to true, the scheduler limits the number of jobs it looks
at during a scheduling run. At the beginning of the scheduling
run it assigns each job a specific category, which is based on
the job's requests, priority settings, and the job owner. All
scheduling policies will assign the same importance to each job
in one category. Therefore the number of jobs per category have
a FIFO order and can be limited to the number of free slots in
the system.
A exception are jobs, which request a resource reservation. They
are included regardless of the number of jobs in a category.
This setting is turned off per default, because in very rare
cases, the scheduler can make a wrong decision. It is also
advised to turn report_pjob_tickets off. Otherwise qstat -ext
can report outdated ticket amounts. The information shown with a
qstat -j for a job, that was excluded in a scheduling run, is
very limited.
PROFILE
If set equal to 1, the scheduler logs profiling information
summarizing each scheduling run.
MONITOR
If set equal to 1, the scheduler records information for each
scheduling run allowing to reproduce job resources utilization
in the file <sge_root>/<cell>/common/schedule.
PE_RANGE_ALG
This parameter sets the algorithm for the pe range computation.
The default is automatic, which means that the scheduler will
select the best one, and it should not be necessary to change it
to a different setting in normal operation. If a custom setting
is needed, the following values are available:
auto : the scheduler selects the best algorithm
least : starts the resource matching with the lowest slot
amount first
bin : starts the resource matching in the middle of the
pe slot range
highest : starts the resource matching with the highest slot
amount first
Changing params will take immediate effect. The default for params is
none.
reprioritize_interval
Interval (HH:MM:SS) to reprioritize jobs on the execution hosts based
on the current ticket amount for the running jobs. If the interval is
set to 00:00:00 the reprioritization is turned off. The default value
is 00:00:00. The reprioritization tickets are calculated by the
scheduler and update events for running jobs are only sent after the
scheduler calculated new values. How often the schedule should
calculate the tickets is defined by the reprioritize_interval. Because
the scheduler is only triggered in a specific interval
(scheduler_interval) this means the reprioritize_interval has only a
meaning if set greater than the scheduler_interval. For example, if
the scheduler_interval is 2 minutes and reprioritize_interval is set to
10 seconds, this means the jobs get re-prioritized every 2 minutes.
report_pjob_tickets
This parameter allows to tune the system's scheduling run time. It is
used to enable / disable the reporting of pending job tickets to the
qmaster. It does not influence the tickets calculation. The sort order
of jobs in qstat and qmon is only based on the submit time, when the
reporting is turned off.
The reporting should be turned off in a system with a very large amount
of jobs by setting this parameter to "false".
halflife_decay_list
The halflife_decay_list allows to configure different decay rates for
the "finished_jobs usage types, which is used in the pending job ticket
calculation to account for jobs which have just ended. This allows the
user the pending jobs algorithm to count finished jobs against a user
or project for a configurable decayed time period. This feature is
turned off by default, and the halftime is used instead.
The halflife_decay_list also allows one to configure different decay
rates for each usage type being tracked (cpu, io, and mem). The list is
specified in the following format:
<USAGE_TYPE>=<TIME>[:<USAGE_TYPE>=<TIME>[:<USAGE_TYPE>=<TIME>]]
<Usage_TYPE> can be one of the following: cpu, io, or mem.
<TIME> can be -1, 0 or a timespan specified in minutes. If <TIME> is
-1, only the usage of currently running jobs is used. 0 means that the
usage is not decayed.
policy_hierarchy
This parameter sets up a dependency chain of ticket based policies.
Each ticket based policy in the dependency chain is influenced by the
previous policies and influences the following policies. A typical
scenario is to assign precedence for the override policy over the
share-based policy. The override policy determines in such a case how
share-based tickets are assigned among jobs of the same user or
project. Note that all policies contribute to the ticket amount
assigned to a particular job regardless of the policy hierarchy
definition. Yet the tickets calculated in each of the policies can be
different depending on "POLICY_HIERARCHY".
The "POLICY_HIERARCHY" parameter can be a up to 3 letter combination of
the first letters of the 3 ticket based policies S(hare-based),
F(unctional) and O(verride). So a value "OFS" means that the override
policy takes precedence over the functional policy, which finally
influences the share-based policy. Less than 3 letters mean that some
of the policies do not influence other policies and also are not
influenced by other policies. So a value of "FS" means that the
functional policy influences the share-based policy and that there is
no interference with the other policies.
The special value "NONE" switches off policy hierarchies.
share_override_tickets
If set to "true" or "1", override tickets of any override object
instance are shared equally among all running jobs associated with the
object. The pending jobs will get as many override tickets, as they
would have, when they were running. If set to "false" or "0", each job
gets the full value of the override tickets associated with the object.
The default value is "true".
share_functional_shares
If set to "true" or "1", functional shares of any functional object
instance are shared among all the jobs associated with the object. If
set to "false" or "0", each job associated with a functional object,
gets the full functional shares of that object. The default value is
"true".
max_functional_jobs_to_schedule
The maximum number of pending jobs to schedule in the functional
policy. The default value is 200.
max_pending_tasks_per_job
The maximum number of subtasks per pending array job to schedule. This
parameter exists in order to reduce scheduling overhead. The default
value is 50.
max_reservation
The maximum number of reservations scheduled within a schedule
interval. When a runnable job can not be started due to a shortage of
resources a reservation can be scheduled instead. A reservation can
cover consumable resources with the global host, any execution host and
any queue. For parallel jobs reservations are done also for slots
resource as specified in sge_pe(5). As job runtime the maximum of the
time specified with -l h_rt=... or -l s_rt=... is assumed. For jobs
that have neither of them the default_duration is assumed.
Reservations prevent jobs of lower priority as specified in
sge_priority(5) from utilizing the reserved resource quota during the
time of reservation. Jobs of lower priority are allowed to utilize
those reserved resources only if their prospective job end is before
the start of the reservation (backfilling). Reservation is done only
for non-immediate jobs (-now no) that request reservation (-R y). If
max_reservation is set to "0" no job reservation is done.
Note, that reservation scheduling can be performance consuming and
hence reservation scheduling is switched off by default. Since
reservation scheduling performance consumption is known to grow with
the number of pending jobs, the use of -R y option is recommended only
for those jobs actually queuing for bottleneck resources. Together
with the max_reservation parameter this technique can be used to narrow
down performance impacts.
default_duration
When job reservation is enabled through max_reservation sched_conf(5)
parameter the default duration is assumed as runtime for jobs that have
neither -l h_rt=... nor -l s_rt=... specified. In contrast to a
h_rt/s_rt time limit the default_duration is not enforced.
FILES
<sge_root>/<cell>/common/sched_configuration
scheduler thread configuration
SEE ALSO
sge_intro(1), qalter(1), qconf(1), qstat(1), qsub(1), complex(5),
queue_conf(5), sge_execd(8), sge_qmaster(8), Sun Grid Engine
Installation and Administration Guide
COPYRIGHT
See sge_intro(1) for a full statement of rights and permissions.