Resource Accounting Policy¶
Starting with the 24th open access grant competition, the accounting policy has been changed from normalized core hours (NCH) to node-hours. This means that it is now required to apply for node hours of the specific cluster and node type:
The accounting runs whenever the nodes are allocated via the PBS Pro workload manager (the qsub command), regardless of whether the nodes are actually used for any calculation.
Conversion Table¶
Resources | Conversion for 1 node-hour |
---|---|
Barbora CPU | 36 core-hours |
Barbora GPU | 4 GPU core-hours |
Barbora FAT | 128 core-hours |
DGX-2 | 16 GPU core-hours |
Karolina CPU | 128 core-hours |
Karolina GPU | 8 GPU core-hours |
Karolina FAT | 768 core-hours |
Original Resource Accounting Policy¶
The original policy, as stated below, is still applied to projects from previous grant competitions.
Wall-Clock Core-Hours WCH¶
The wall-clock core-hours (WCH) are the basic metric of computer utilization time. 1 wall-clock core-hour is defined as 1 processor core allocated for 1 hour of wall-clock time. For example, allocating a full node (i.e. 36 cores) on Barbora for 1 hour amounts to 36 wall-clock core-hours.
Normalized Core-Hours NCH¶
The resources subject to accounting are the normalized core-hours (NCH). The normalized core-hours are obtained from WCH by applying a normalization factor:
All jobs are accounted in normalized core-hours, using factor F valid at the time of the execution:
System | F | Validity |
---|---|---|
Karolina | 1.00 | 2021-08-02 to 2022-09-06 |
Barbora CPU | 1.40 | 2020-02-01 to 2022-09-06 |
Barbora GPU | 4.50 | 2020-04-01 to 2022-09-06 |
DGX-2 | 5.50 | 2020-04-01 to 2022-09-06 |
The normalized core-hours were introduced to treat systems of different age on equal footing. Normalized core-hour is an accounting tool to discount the legacy systems.
See examples in the Job submission and execution section.
Consumed Resources¶
Check how many core-hours have been consumed. The command it4ifree
is available on cluster login nodes.
$ it4ifree
Projects I am participating in
==============================
PID Days left Total Used WCHs Used NCHs WCHs by me NCHs by me Free
---------- ----------- ------- ----------- ----------- ------------ ------------ -------
OPEN-XX-XX 323 0 5169947 5169947 50001 50001 1292555
Projects I am Primarily Investigating
=====================================
PID Login Used WCHs Used NCHs
---------- ---------- ----------- -----------
OPEN-XX-XX user1 376670 376670
user2 4793277 4793277
Legend
======
WCH = Wall-clock Core Hour
NCH = Normalized Core Hour
The it4ifree
command is a part of the it4i.portal.clients
package, located here.