Difference between revisions of "HPRC:AMS:Functionality"
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Revision as of 15:42, 23 September 2014
At the present stage of development, AMS is able to manage and report the status of both your login accounts and your resources granted on each of the Supercomputing Facility system.
AMS provides an easy way of managing your credentials to access any of the available systems at the Supercomputing Facility.
If you are granted access to one of our machines for the first time, you may create your login id and set up your password for that machine using the AMS web interface.
Please note that, while we recommend using different password for better protection of your data, you are allowed to have only a unique login id on all the systems of the Supercomputing Facility.
If you already have a login on one of our machines, you may change your password through AMS.
You may also set a few preferences in your personal profile page. At this moment, you have the possibility of choosing whether or not you wish to receive our announcements to your email account.
Manage your accounts
Manage your granted computing time and report your usage with AMS. AMS allows you to flexibly manage the computing time you have been granted for each the different machines of our Supercomputing Facility upon approval of your application.
Computing time is granted and measured in billing units (BU). Each BU corresponds to 1 hour of wall clock time elapsed on 1 cpu-core by your application. The amount of resources used by your jobs is billed to a personal billing account.
A personal billing account is created for each machine requested in your application when you apply for the first time. A billing account allows you to keep track of all the BUs granted to you and used by you on a given machine. It is usually assigned to you for the duration of your project, but it expires at the end of each accounting period. Currently, an accounting period spans an entire school year, running from September 1st to August 31st of the next year. For such reason, we will refer to it as fiscal year (FY).
For your convenience, billing accounts are tied to the reason of your request of computing time. Therefore, you may assign to your billing account a description related to your intended usage of the machine. For instance, you may use the title of a personal research project, or mention a class you are attending, etc.
If you reapply in the near future for the same research project, you may be allowed to continue to use the same billing account number assigned to you for that project during the previous accounting period.
If you are a Principal Investigator (PI), and you manage a group of users working on a single research project, you may transfer BUs to your researchers' billing accounts using your AMS personal web interface. You may also reclaim your transferred BUs and redistribute them later on according to your needs.
You should always select which one of your billing account you wish your used resources should be billed to. On eos, the billing account may be specified by including the special PBS resource billto= in your list of requested resources (option -l).
For your convenience, however, you may designate a primary billing account, which will be used as your default account when you don't specify any account number. Currently, you may only set your primary account using the command line interface (myams -p).
If you have only one billing account, then this account is automatically set as primary and your usage billed to it by default.
Once you submit a job to our batch system, AMS computes a charge in BUs based on the amount of resources (wall clock time and number of cpu cores) requested by your batch job file. The balance of your selected billing account is then checked to determine if you have enough BUs left to accommodate this charge (This check is done for each job step included in your job command file on hydra). If your available balance is large enough, the charge is posted to the billing account as pending. Once your job has exited the batch system, this pending charge is dismissed and a new charge reflecting the actual usage is billed as final.
If your billing account does not contain enough BUs to satisfy what requested in your job command file, your job submission will be rejected by the batch system until your account will be replenished.
For such reason, we strongly encourage you to request an amount of resources very close to what you estimate your job will actually need.
Also, you will not be allowed to use the batch system after your billing account has expired. However, you may continue to login on the system and work on your files until your login id expires.
Currently, the expiration date of your login id is set by default to October 1st.