User-Settable Reservations through SDSC User Portal
The Reservations Portlet allows you to reserve nodes in advance on the TeraGrid IA-64 Cluster. From the portal, you can see which nodes are available in an easy calendar format. You may choose the number of nodes, the start time, and the duration of the reservation in a Web form and get an immediate confirmation without e-mail to the help desk. Once a successful reservation is made, you may run any number of jobs under that reservation. Some of the advantages are outlined below.
Advantages
- Reservations enable you to set a definite start time for jobs, allowing you more control of your work schedule. Computing time can be planned in conjunction with other tasks, such as experimental research work, demos, and classes.
- Reservation of nodes for large jobs can allow more efficient use of time when debugging run-time problems that appear only at large scales. This is especially useful if you need to run jobs that will take up most of the machine. When submitting jobs to the queue normally, you may find that a sufficient number of nodes is no longer available after you have stopped a job to debug because another user's job has started to run. With a reservation, your work can continue uninterrupted.
- You can run multiple jobs within a reservation, allowing multiple dependent runs without the delay associated with scheduling such jobs via the regular queue.
Recommended Use for the User Settable Reservations Portlet
Setting your own reservations through the SDSC Portal is recommended for medium to large jobs that need to be run at specific times due to staffing constraints or workflow dependencies. It is not recommended for small serial jobs that could be run efficiently using the normal queues. There is a minimum job size of 16 SUs (1 hour or 8 CPUs minimum). See the Reservation Policies for more details.
How to Make and Cancel Reservations through the User-Settable Reservations Portlet
User Settable Reservations allow you to make reservations based on availability of time and on your remaining allocation time. From the reservations portal, click on the tab for the machine on which you wish to reserve time. Fill out the preliminary fields so that the portal can find all the available opportunities that match your needs. It also pulls up your project numbers so that you can assign the job to the right one.
Once the portal displays the opportunities, choose one and fill out the required information on the right. You can change the number of nodes; however, your request must comply with the policies for the machine.
See the documentation in the portal for specific instructions, policies, and charges.
How It Works
Both User-Settable Reservations and Cross-Site Co-Scheduling portlets utilize technologies such as TeraGrid Single Sign-On, GridSphere portal framework and GridPortlets API, MyProxy X.509 certificate management, Globus middleware, and job schedulers such as Catalina and Moab. For detailed functional and architectural design, please see TG '08 Reservations Poster [PDF].
