DESCRIPTION

This page summarizes the resources and special features supported by PBS for Cray Research computers running Unicos versions 8 and 9. These resources are specified by including them in the -l option argument on the qsub or qalter command or in the PBS job script.

RESOURCES

ncpus

Maximum number of multitask processes in the job. If this is set the environment variable NCPUS will be set to the given value. Units: unitary.

cput

Maximum amount of CPU time used by all processes in the job. Root processes are not limited, see limit(2). Units: time.

mem

Maximum amount of physical memory used by all concurrent processes in the job. Units: size.

mppe

The number of processing elements used by a single process in the job. Units: unitary.

mppt

Maximum amount of wall clock time used on the MPP in the job. Units: time.

mta, mtb, mtc, ..., mth

Maximum number of magnetic tape drives required in the corresponding device class of a, b, c, ..., h. Units: unitary.

nice

The nice value under which the job is to be run. Units: unitary.

pncpus

Maximum number of processors used by any single process in the job. Units: unitary.

pcput

Maximum amount of CPU time used by any single process in the job. Units: time.

pf

Maximum number of file system blocks that can be used by all process in the job. Units: size.

pmem

Maximum amount of physical memory used by any single process in the job. Units: size.

pmppt

Maximum amount of wall clock time used on the MPP by a single process in the job. Units: time.

ppf

Maximum number of file system blocks that can be used by a single process in the job. Units: size.

procs

Maximum number of processes in the job. Units: unitary.

psds

Maximum number of data blocks on the SDS (secondary data storage) for any process in the job.

sds

Maximum number of data blocks on the SDS (secondary data storage) for the job.

srfs_tmp

Session Reservable File System (SRFS) space in TMPDIR. Note, SRFS is not supported by Cray. Units: size.

srfs_wrk

SRFS space in WRKDIR. Units: size.

srfs_big

SRFS space in BIGDIR. Units: size.

srfs_fast

SRFS space in FASTDIR. Units: size.

walltime

Maximum amount of real time during which the job can be in the running state. Units: time.

arch

Specifies the administrator defined system architecture requried. This defaults to whatever the PBS_MACH string is set to in "local.mk". Units: string.

host

Name of host on which job should be run. This resource is provided for use by the site's scheduling policy. The allowable values and effect on job placement is site dependent. Units: string.

nodes

Number and/or type of nodes to be reserved for exclusive use by the job. The value is one or more node_specs joined with the '+' character, "node_spec[+node_spec...]. Each node_spec is an number of nodes required of the type declared in the node_spec and a name or one or more properity or properities desired for the nodes. The number, the name, and each properity in the node_spec are separated by a colon ':'. If no number is specified, one (1) is assumed. Units: string.

The name of a node is its hostname. The properities of nodes are:

.

ppn=# specifying the number of processors per node requested. Defaults to 1.

.

arbitrary string assigned by the system administrator, please check with your administrator as to the node names and properities available to you.

Examples:

.

To ask for 12 nodes of any type: -l nodes=12

.

To ask for 2 "server" nodes and 14 other nodes (a total of 16): -l nodes=2:server+14
The above consist of two node_specs "2:server" and "14".

.

To ask for (a) 1 node that is a "server" and has a "hippi" interface, (b) 10 nodes that are not servers, and (c) 3 nodes that have a large amount of memory an have hippi:
-l nodes=server:hippi+10:noserver+3:bigmem:hippi

.

To ask for three nodes by name:
-l nodes=b2005+b1803+b1813

.

To ask for 2 processors on each of four nodes:
-l nodes=4:ppn=2

.

To ask for 4 processors on one node:
-l nodes=1:ppn=4

.

To ask for 2 processors on each of two blue nodes and three processors on one red node:
-l nodes=2:blue:ppn=2+red:ppn=3

host

Allows a user to specify the desired execution location. This resource is provided for use by the site's scheduling policy. The allowable values and effect on job placement is site dependent. Units: string.

other

Allows a user to specify site specific information. This resource is provided for use by the site's scheduling policy. The allowable values and effect on job placement is site dependent. Units: string.

software

Allows a user to specify software required by the job. This is useful if certain software packages are only available on certain systems in the site. This resource is provided for use by the site's scheduling policy. The allowable values and effect on job placement is site dependent. Units: string.

EXAMPLES

qsub -l nodes=15,walltime=2:00:00 script

or in a qsub script as a directive:

#PBS -l nodes=15,walltime=2:00:00

qsub -l cput=1:00:00,pcput=20:00,file=50gb,mem=15mb,mta=2 script
qalter -lcput=30:00,pmem=8mb 123.jobid
qsub -lsrfs_tmp=50mb,srfs_big=2gw script

or in a qsub script as directives:

#PBS -l cput=1:00:00,pcput=20:00,file=50gb,mem=15mb,mta=2
#PBS -lsrfs_tmp=50mb,srfs_big=2gw

SPECIAL FEATURES

Cray Unicos supports checkpoint and restart. Any description of checkpoint features in PBS are applicable to Unicos.

RESOURCE UNITS

The resource values take the following units:

time

specifies a maximum time period the resource can be used. Time is expressed in seconds as an integer, or in the form:

size

specifies the maximum amount in terms of bytes or words. It is expressed in the form The suffix is a multiplier defined in the following table, The size of a word is the word size on the execution host.

 b or  w

bytes or words.

kb or kw

Kilo (1024) bytes or words.

mb or mw

Mega (1,048,576) bytes or words.

gb or gw

Giga (1,073,741,824) bytes or words.

unitary

The maximum amount of a resource which is expressed as a simple integer.