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New job queue setup: queue by job duration, not by VO

During yesterday's scheduled maintenance, a major change has been implemented for LHC VOs: jobs queues are now organized by duration, not by VO. The longest-running queue has the same limits that were formerly imposed on the VO-specific queues.

The reason for this change was to allow jobs to use the cluster until the "last minute" when the cluster nodes are reserved for planned downtimes.

The new queue setup requires proper specification of the job running time in the JDL file, otherwise your job may land in short time queue, and be killed before completion since it ran out of CPU time.

Instructions on how to properly specify job duration requirements are given below.

For more information, feel free to write an email to lcg@cscs.ch.

The new queues

The new queues have been given names that reflect the alloted CPU time (e.g., egee8h is for jobs using up to 8 hours of CPU time); the maximum wall-clock time has been computed by augmenting the CPU time by ~20%, with more leeway for shorter queues. (The rationale being that the excess wall-clock time is usually spent moving data to an SE; for shorter jobs, this will take a larger fraction of the total running time.)

JDL requirements syntax

In order to ensure that your job gets enough CPU or wall-clock time, a requirement must be stated using the Requirements attribute in the JDL file.

To specify that a job needs at least 120 minutes of CPU time, use the following line in your JDL file:

Requirements = other.GlueCEPolicyMaxCPUTime > 120

To specify that a job needs at least 180 minutes of wall-clock time, use the following line in your JDL file:

Requirements = other.GlueCEPolicyMaxWallClockTime > 180

Requirements can be combined with the boolean && (and) and || (or) operators, so you can also specify that a job needs at least 120 minutes of CPU time, and 180 minutes of wall-clock time:

Requirements = (other.GlueCEPolicyMaxCPUTime > 120) && (other.GlueCEPolicyMaxWallClockTime > 180)

-- RiccardoMurri - 30 Sep 2008