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--- services:computing:hpc [2021/09/06 12:09]
calucci [Queue System] power9
+++ services:computing:hpc [2022/02/11 15:20]
calucci email reports
@@ Line 23: / Line 23: @@
 The software tree is the same you have on Linux workstations, with the same [[services:modules|Lmod modules]] system (with the only exception of desktop-oriented software packages).
-A small number of POWER9-based nodes are also available (2 sockets, 16 cores, 4 threads per core; 256GB RAM). Please note that you cannot run x86 code on POWER9.
+A small number of POWER9-based nodes are also available (2 sockets, 16 cores, 4 threads per core; 256GB RAM) with 2 or 4 Tesla V100. Please note that you cannot run x86 code on POWER9. For an interactive shell on a P9 machine, please type ''p9login'' on frontend[12].
 ===== Queue System =====
@@ Line 87: / Line 87: @@
 Due to their inherent volatility, some directories can be excluded from the backup set. At this time, the list of excluded directories includes only one item, namely ''/home/$USER/.cache''
+===== Job E-Mail =====
+You can enable e-mail notifications at various stages of each job life with the ''--mail-type=TYPE'' option where ''TYPE'' can be a comma-separated list such as ''BEGIN,END,FAIL'' (more details are available in ''man sbatch''). Notification recipient is by default your SISSA e-mail address, but you can select a different address with ''--mail-user''. **End-job** notification includes a summary of consumed resources (CPU time and memory) as absolute values and as a percentage of requested resources. Please note that memory usage is sampled at 30 seconds intervals, so if your job is terminated by an out-of-memory condition arising from a very large failed allocation, the reported value can be grossly underestimated.
+==== Energy Accounting ====
+An experimental energy accounting system has been enabled on Ulysses, and energy usage estimates are reported in end-job notification. This is intended as a very rough estimate of the energy impact your job has, but is **not** accurate enough to be used for proper cost/energy/environmental accounting. Known limits of the energy accounting system in use include:
+  * very small values are completely unreliable (and are not included at all in the end-job notification, so in case of very short or "mostly idle" job you will find no value at all)
+  * only CPU and memory energy usage are considered, while energy consumed by other devices (network cards, disk controllers, service processors, power supplies) is not accounted for; energy used "outside" the compute nodes is not considered as well (this include network devices, external storage, UPS, HVAC), so even for a CPU-intensive job the "real" energy consumption can easily be twice as much than reported
+  * on the other side, //if your job doesn't use all available cores on each allocated node//, energy consumption can be overestimated
 ===== Reporting Issues =====
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 When reporting issues with Ulysses, please keep to the following guidelines:
-  * write to [[helpdesk-hpc@sissa.it]], not to personal email addresses: this way your enquiry will be seen by more than one person
+  * write to [[helpdesk-hpc@sissa.it]], not to personal email addresses: this way your request will be seen by more than one person
   * please use a clear and descriptive subject for your message: "missing library libwhatever.so.12 from package whatever-libs" is OK, "missing software" is less useful, "Ulysses issues" is definitely not useful
   * please open one ticket for each issue; **do not** reply to old, closed tickets for unrelated issues