2024-06-20
In TSUBAME application use, there are some applications where a small number of users occupy licenses.
We have established a Limitation of Licenses for applications that tend to have insufficient number of licenses for the number of users.
The current Abaqus license limit is 140 Token per user, but this was based on the queue configuration in TSUBAME2 and TSUBAME3 and the old Abaqus license management, so this will be changed to 120 Token per user.
Since the total number of tokens is 500, up to three jobs with 140 tokens can run concurrently, while up to four jobs with 120 tokens can run concurrently.This allows more users to use the system at the same time.
The table below shows the relationship between the number of Abaqus parallels, the number of licenses used, and the execution time of the sample program. The table includes errors due to the small number of trials, and some values may be reversed, but please use it as a reference.
| Number of CPUs (GPU also counted as 1) | Number of Tokens | Resource types | Execution time (s) |
|---|---|---|---|
| 1 | 50 | cpu_4 | 524 |
| 2 | 59 | cpu_4 | 265 |
| 3 | 67 | cpu_4 | 179 |
| 4 | 76 | cpu_4 | 136 |
| 5 | 85 | cpu_8 | 112 |
| 6 | 94 | cpu_8 | 94 |
| 7 | 103 | cpu_8 | 87 |
| 8 | 112 | cpu_8 | 81 |
| 8+1GPU | 120 | gpu_1 | 61 |
| 9 | 120 | cpu_16 | 73 |
| 10 | 125 | cpu_16 | 79 |
| 11 | 130 | cpu_16 | 71 |
| 12 | 135 | cpu_16 | 68 |
| 13 | 140 | cpu_16 | 66 |
The current limit of 140 Token allows one job with a maximum of 13 CPUs, but the new limit of 120 Token allows one job with a maximum of 9 CPUs. 2 jobs with 1 CPU or 2 CPUs can be executed simultaneously.
To run a 13-CPU job, the cpu_16 resource type must be specified, which doubles the billing factor compared to an 8-CPU job with the cpu_8 resource type, but is inefficient because the difference in execution time is only about 20%. The fastest and most efficient execution can be expected by specifying the resource type cpu_8 for an 8 CPU job.
Since it cannot be denied that the computation time will still be longer than before, we have decided to use 120 tokens, leaving room for gpu_1 (8CPU+1GPU). 1GPU has an effect similar to doubling the number of CPUs and improves the efficiency per license number, but please note that in this case, the charge factor based on the resource type will be much higher. If speed is not required, the maximum efficiency is achieved by using 4 CPUs with the resource type cpu_4.
In the future, as with TSUBAME3, we plan to systematically disallow the use of licenses that exceed the limit, but currently it is possible to run licenses in excess of the limit.
We expect that lowering the limit will improve the license shortage situation as it will provide more leeway, but as mentioned above, the systemic limit has not yet been implemented, so we need the cooperation of all users.
If a job is found to be running over the limit, the job may be terminated without refusal. If such a situation is observed on an ongoing basis, access to purchased applications may be blocked.
We ask that you use this service with caution.