G. Special Considerations

1. Core Memory for Batch Jobs

CCN can easily run batch jobs requiring up to 3 million bytes, although jobs over 600K bytes will normally not run during prime time.

2. Disk Space

CCN provides extensive on-line disk space for permanent files. The resident disk pack configuration includes:

220 M bytes (8 packs) of user source programs, for use through URSA.

170 M bytes (6 packs) of user object and load modules ("binary decks") and other files.

100 M bytes of limited-time storage (n days, where n is published number satisfying 7<= n < 0)

This space is charged for, at about 5s per kilobyte per month.

In the future, we plan to significantly extend this on-line space by implementing a tertiary storage system using magnetic tapes. In addition, a batch job may always request that the user's own disk pack be mounted, thus allowing very large private collections of files.

3. Rates

Batch charges are based upon t(CPU time), I(number of I/O requests), and R(core memory region size). The current rate schedule may be obtained from:

           Mr. Kenneth Tom
           User Relations Supervisor
           UCLA
           Campus Computing Network
           Math Sciences Addition
           Los Angeles, California 90024

Generally speaking, the CCN Model 91 cost is very attractive for compute-bound, heavy floating-point calculations, particularly where large regions are required. For most other jobs, the CCN machine is competitive with other cost-recovery computing centers which operate without special subsidy.