Synopsis
Jobs can have requirements, which are resources or other conditions which must be available before the job can run. Qube!'s requirement specification is expression based. The syntax for specifying the expression is similar to Perl or C. The proper use of these expressions will allow a user to specify the host and/or the conditions required before a job is allowed to run. The syntax for specifying the expression is similar to Perl or C. The evaluation of the expression where:
<expression> == true
allows the job to be dispatched to a qualifying host. An expression consists of operators and operands. Operators are either text or symbolic.
These are equivalent:
eq, ==, =
String and numeric comparisons are automatically resolved based upon the values they resolve to.
Quoting
Since a job requirement can include a number of operator characters, any reference to a property or resource that includes an operator should be quoted so the interpreter can differentiate between the literal character and the operator.
Example
$ qbsub --requirements "host.kernel_version eq '2.6.17-1.2142_FC4smp'"
Operators
Operator | Definition | Expression | Result |
|---|---|---|---|
min | minimum | 10 min 12 | 10 |
max | maximum | 10 max 12 | 12 |
sub, - | subtract | 10 sub 8 | 2 |
add, + | addition | 1 + 2 | 3 |
mul, * | multiplication | 3 * 4 | 12 |
div, / | division | 14 / 7 | 2 |
xor, ^ | XOR | 12 xor 8 | 4 |
mod, % | modulus | 10 % 4 | 2 |
in | value in list (string with commas) | "v" in "x,y,v" | true |
has | list (string with commas) has value | "x,y,v" has "v" | true |
not, ! | NOT | not 1 | false |
eq, =, == | equal | 10 == 10 | true |
ne, <>, != | NOT equal | 10 != 10 | false |
and, && | AND | 1 and 0 | false |
| or, || | OR | 1 or 0 | true |
& | bitwise AND | 12 & 8 | 8 |
| | | bitwise OR | 8 | 4 | 12 |
lt, < | less than | 5 < 10 | true |
gt, > | greater than | 5 > 10 | false |
le, <= | less than or equal | 4 >= 6 | false |
ge, >= | greater than or equal | 4 <= 6 | true |
rs, >> | bitwise right shift (used to divide by 2n) | 4 >> 1 | 2 |
ls, << | bitwise left shift (used to multiply by 2n) | 4 << 1 | 8 |
The reason for multiple definitions for most operators is to allow a programmer more flexibility in the case of Unix command line applications where reserved characters like the such as ">", unless otherwise escaped, will be interpreted by the shell.
Operands
Operands in Qube! also have a syntax. They all follow a base class.type format.
Host.type operands
Operand | Values |
|---|---|
host.os | "linux", "irix", "winnt", "osx" |
host.processor_speed | CPU speed in MHz |
host.processor_make | "GenuineIntel", "AuthenticAMD" |
host.processor_model | "pentium" |
host.kernel_version | Version reported by the operating system. |
host.architecture | "intel", "mips" |
host.name | Host name |
host.groups | Comma delimited list of group names |
host.cluster | Cluster specification string |
host.state | Host state |
host.restrictions | List of restricted cluster specification strings |
host.flags | Numeric representation of the Worker's flags |
host.qube_version | Worker version of Qube! |
host.jobtypes | Comma delimited list of job types |
host.flag.name | true if the flag exists |
host.duty.property | Comma delimited list of job properties for jobs on the worker. |
Example
Here are some examples of job requirements that include property expressions:
% qbsub --requirements "host.os eq linux" ls % qbsub --requirements "host.name eq host01" ls % qbsub --requirements "host.flag.remove_logs host.group has host05" ls % qbsub --requirements "(host.os == 'winnt') and host.processor_speed >= 100" ls
Resource operands
are slightly different and include those defined by your administrator host.
Operand (resource) | Values |
|---|---|
host.processors.[ used | avail | total ] | Number of processors available on the worker |
host.memory.[ used | avail | total ] | Memory in Mb available on the worker |
host.swap.[ used | avail | total ] | Swap space available in Mb on the worker |
Example
Here is an example of a job requirement that uses a host resource expression:
% qbsub --requirements "host.processors.total > 10" ls
Job operands
The possible operands for a job.type are:
Operand | Description |
|---|---|
job.name | job name |
job.id | job id |
job.pid | job's parent id |
job.pgrp | job process group |
job.priority | job priority |
job.label | job's label |
job.user | job's owner |
job.status | job status |
job.prototype,job.type | job type |
job.cluster | job's cluster value |
job.restrictions | restrictions list |
job.kind | user defined job "kind" |
job.reservations | job's reservations |
job.requirements | job's requirements |
job.flags | job's flags numeric value |
job.flag.[name] | true if the flag exists |
| job.kind | job kind |
...
Examples
| Syntax | Explanation |
|---|---|
% qbsub --requirements " |
...
host. |
...
Requirements Expressions - Advanced Examples
More advanced uses of the requirements expression allow Qube! users to route a job to a specific host and also conversely restrict a job from a host.
Common Uses:
processors.total > 10" set | Command line example that uses a host resource expression |
host.os eq linux | Run my job only on |
...
| Linux hosts |
...
"host.os |
...
== 'winnt' and host.processor_speed >= 3000" | Run |
...
| on a Windows machine that has a processor speed of at least 3GHz | |
host.name ne "qb001" | Run |
...
| my job on |
...
| any host except qb001 | |
"maya" in host.jobtypes | Run |
...
| the job |
...
| on a host with the Maya job type | |
host.processors.total == 2 | Run my job only |
...
| on dual processor hosts | |
not (job.id in host.duty.id) | Run my job only |
...
| if there isn't already one of this job's instances running on it | |
(Also see How to restrict a host to only one instance of a given kind of job, but still allow other jobs) | Run only one "kind" of job on a worker at the same time |