Job charging based on usage

Jobs are charged based length, number of cores, amount of memory, single node versus multi-node, and type of resource.

Length and number of cores

Jobs are recorded in terms of core-hours hours used. Core-hours can be calculated by:

number of cores * length of job

e.g.

A 4 core job that runs for 2 hours would have a total core-hour usage of:

4 cores * 2 hours = 8 core-hours

Amount of Memory

Each processor has a default amount of memory paired along with it, which differs by cluster. When requesting a specifc amount of memory that doesn't correlate with the default pairing, the charging uses an algorithm to determine if the effective cores should be used.

The value for effective cores will be used in place of the actual cores used if and only if it is larger than the explicit number of cores requested.

effective cores = memory / memory per core

e.g.

A job that requests  nodes=1:ppn=3  will still be charged for 3 cores of usage.

However, a job that requests  nodes=1:ppn=1,mem=12GB, where the default memory allocated per core is 4GB, then the job will be charged for 3 cores worth of usage.

effective cores = 12GB / (4GB/core) = 3 core

Single versus Multi-Node

If requesting a single node, then a job is charged for only the cores/processors requested. However, when requesting multiple nodes the job is charged for each entire node regardless of the number of cores/processors requested.

Type of resource

Depending on the type of node requested, it can change the dollar rate charged per core-hour. There are currently three types of nodes, regular, hugememory,and gpu.

If a gpu node is used, there are two metrics recorded, core-hours and gpu-hours. Each has a different dollar-rate, and these are combined to determine the total charges for usage.

e.g.

A job requests nodes=1:ppn=8:gpus=2 and runs for 1 hour.

The usage charge would be calculated using:

8 cores * 1 hour = 8 core-hours

and

2 gpus * 1 hour = 2 gpu-hours

and combined for:

8 core-hours + 2 gpu-hours

Project storage charging based on quota

Projects that request extra storage be added are charged for that storage based on the total space reserved (i.e. your quota). 

The rates are in TB per month:

storage quota in TB * rate per month