Credit Account Charges¶
Credits may be requested and used under the CPU Credit category or the GPU Credit category. Credits are specific to each node type – CPU Credits are not transferable to GPU Credits, and vice-versa. CPU Credit charges are defined by a combination of per-job cores and memory request, while GPU Credit charges are defined by a combination of per-job GPU, CPU, and memory request.
CPU Credits¶
| Cores per job | Credit charge per core hour |
|---|---|
| 1 | 1.0 |
| 2-8 | 1.2 |
| 8-32 | 1.5 |
| >32 | 2.0 |
When running on a resource with hyperthreaded cores, a 40% discount is applied; e.g., 1 hyperthreaded core for 1 hour costs 0.6 credits.
Additional CPU Credit Charge¶
Memory Per Core¶
When more than 2GB per core of memory is requested by the job, there’s an additional per-GB charge for memory.
| Memory (GB) per job | Credit charge per hour, per GB |
|---|---|
| Up to 2GB per core ("nominal") | No charge |
| 2-8 GB greater then nominal | 0.125 |
| 8-32 | 0.25 |
| 32-128 | 0.375 |
| 128-512 | 0.50 |
CPU Credit Example¶
If an 8 core job requests 128 GB of RAM, there is an additional charge for 128 – (8 * 2) = 112 GB of RAM. If the job ran for an hour, it would use 0.375 * 112 = 42 credits total for memory and 1.2 * 8 = 9.6 credits for CPU.
GPU Credits¶
| GPUs per job | Credit charge per GPU hour |
|---|---|
| 1 | 1.0 |
| 2 | 1.2 |
| 3 | 1.5 |
| 4 | 2.0 |
Additional GPU Credit Charge¶
CPUS per GPU¶
When more than 16 cores per GPU is requested by the job, there’s an additional per-core charge for the CPU cores beyond the nominal.
| CPUs per GPU | Credit charge per hour, per core |
|---|---|
| Up to 16 cores per GPU ("nominal") | No charge |
| 16-48 cores per GPU | 0.125 |
| 48-64 | 0.20 |
Memory per GPU¶
When more than 2 GB per core of memory is requested by the job, there’s an additional per-GB charge for memory for the beyond-nominal memory usage.
| Memory (GB) per job | Credit charge per hour, per GB |
|---|---|
| Up to 128GB per GPU ("nominal") | No charge |
| 128-384 GB per GPU | 0.012 |
| 384-512 | 0.020 |
GPU Credit Example¶
If a 1 GPU job requests 256 GB of RAM and 32 cores, there is an additional charge for 256 – (1 * 128) = 128 GB of RAM and an additional charge for 32 – (1 * 16) = 16 cores. If the job ran for an hour, it would use 0.012 * 128 = 1.536 credits total for memory, 0.125 * 16 = 2 credits for CPU, and 1.0 * 1 = 1.0 credits for GPU.