Cray xc40 using the batch system – hlrs platforms

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Additionally you have to know that on CRAY XE6/XC40 systems the user applications are always launched on the compute nodes using the application launcher, aprun, which submits applications to the Application Level Placement Scheduler (ALPS) for placement and execution.

Detailed information for CRAY XC40 about how to use this system and many examples can be found in Cray Programming Environment User’s Guide and Workload Management and Application Placement for the Cray Linux Environment.

• Thread A thread is contained inside a process.


Call option Multiple threads can exist within the same process and share resources such as memory, while different PEs do not share these resources. Eur usd exchange rate Most likely you will use OpenMP threads.

You generally interact with the batch system in two ways: through options specified in job submission scripts (these are detailed below in the examples) and by using torque or moab commands on the login nodes. Market futures for tomorrow There are three key commands used to interact with torque:

Production jobs are typically run in batch mode. 256 in binary Batch scripts are shell scripts containing flags and commands to be interpreted by a shell and are used to run a set of commands in sequence.

• The number of required nodes, cores, wall time and more can be determined by the parameters in the job script header with “#PBS” before any executable commands in the script.

• The batch script is not necessarily granted resources immediately, it may sit in the queue of pending jobs for some time before its required resources become available.

• This example will run your executable “my_mpi_executable” in parallel with 48 MPI processes. Usd rmb exchange rate history Torque will allocate 2 nodes to your job for a maximum time of 20 minutes and place 24 processes on each node (one per core). 1 usd to inr today The batch systems allocates nodes exclusively only for one job. Live futures market After the walltime limit is exceeded, the batch system will terminate your job. Binary coder The job launcher for the XC40 parallel jobs (both MPI and OpenMP) is aprun. Futures market explained This needs to be started from a subdirectory of the /mnt/lustre_server (your workspace). Sftp binary mode The aprun example above will start the parallel executable “my_mpi_executable” with the arguments “arg1” and “arg2”. Binary explained The job will be started using 48 MPI processes with 24 processes placed on each of your allocated nodes (remember that a node consists of 24 cores in the XC40 system). Future stock market You need to have nodes allocated by the batch system (qsub) before starting aprun.

Interactive mode is typically used for debugging or optimizing code but not for running production code. What is the binary system To begin an interactive session, use the “qsub -I” command:

If the requested resources are available and free (in the example above: 2 nodes/24 cores, 30 minutes), then you will get a new session on the mom node for your requested resources.

• Remember, you use aprun within the context of a batch session and the maximum size of the job is determined by the resources you requested when you launched the batch session. Us exchange rate to canadian dollar You cannot use the aprun command to use more resources than you reserved using the qsub command. Gold background images Once a batch session begins, you can only use the resources initially requested or less resources.

• While your job is running (in Batch Mode), STDOUT and STDERR are written to a file or files in a system directory and the output is copied to your submission directory only after the job completes. Usd nzd Specifying the “qsub -j oe” option here and redirecting the output to a file (see examples above) makes it possible for you to view STDOUT and STDERR while the job is running.

Note: be aware that the output of all these commands show a state of the system at the moment when the command is issued. Equity meaning in accounting The starting time of jobs for instance also depends on other events like jobs submitted in the future which may fit better into the scheduling of the machine, on the shape of the hardware, other queues and reservations…

• Resource Utilization Reporting (RUR) is a tool for gathering statistics on how system resources are being used by applications. Cnn world market futures AT HLRS RUR is configured to write a single file in user home directory: rur.out. Exchange rate usd to cad history The content of the file is the output of each plugin used by RUR. Usd rate The plugins are: “taskstats”, “energy” and “timestamp”.

The numbering of the cores in single stream mode is 0-11 for die 0 and 12-23 for die 1. 10110 binary If using dual stream mode the numbering of the first 24 cores stays the same and cores 24-35 are on die 0 and 36-47 on die 1. Rs to usd exchange rate Note that this makes the numbering of the cores in hypterthread mode not contiguous:

For 24-CPU Cray XC40 compute node processors, NUMA nodes 0 and 1 have 12 CPUs each (logical CPUs 0-11, 12-23 respectively). Xpf to usd If your applications use Intel Hyperthreading Technology, it is possible to use up to 48 processing elements (logical CPUs 0-11 as well as 24-35 are on NUMA node 0 and CPUs 12-23 as well as 36-48 are on NUMA node 1).

Intel RTE creates one extra thread when spawning the worker threads. Exchange rate us to pound This makes the correct, efficient, pinning more difficult for aprun. Price of gold dubai In the default setting this extra thread is scheduled as second thread. Binary convert to text In the default setting ( OMP_NUM_THREADS=$omps and aprun -d $num_d) the threads are scheduled round robin, the extra thread on the second cpu, while at the end two application threads (first and last one) are both placed on the first cpu. Video editor windows free This results in a significant performance degradation.

But this extra thread usually has no significant workload. Funny quotes about work stress Thus, this extra thread does not influence the performance of an application thread, when it is located on the same cpu.

CLE was updated to allow threads and processing elements to have more flexibility in placement. Goldman sachs gold forecast 2016 This is ideal for processor architectures whose cores share resources with which they may have to wait to utilize. Funny jokes in urdu Separating cpu_lists by colons (:) allows the user to specify the cores used by processing elements and their child processes or threads.

The aprun allows to start an application with more OpenMP threads than compute cores available. Convert 3000 euros to us dollars This oversubscription results in a substantial performance degradation. Binary counters The same happens if the -d value is smaller than the number of OpenMP threads used by the application. Python tutorial pdf Furthermore, for the Intel programming environment an additional helper thread per processing element is spawned which can lead to an oversubscription. Coffee futures market news Here, one can use the -cc numa_node or the -cc none option to aprun to avoid this oversubscription of hardware. Usa today high school football rankings 2016 The default behavior, i.e. 500 usd if no -cc is specified, is as if -cc cpu is used which means that each processing element and thread is pinned to a processor. Euro vs usd exchange rate Please consult the aprun man page. Binary search Another popular option to aprun is -ss which forces memory allocation to be constrained in the same node as the processing element or thread is constrained. Eur usd live chart One can use the xthi.c utility to check the affinity of threads and processing elements.


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