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en:services:application_services:high_performance_computing:running_jobs_slurm [2019/04/03 10:17]
mboden [Available Queues]
en:services:application_services:high_performance_computing:running_jobs_slurm [2020/04/14 14:47] (current)
mboden [''sbatch'': Specifying node properties with ''-C'']
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-======First docu (not yet released) ====== +====== Running Jobs with SLURM======
-====== Running Jobs ======+
  
 In the following the basic concepts will be described. In the following the basic concepts will be described.
  
 **Cluster**\\ **Cluster**\\
-A collection of networked computers intended to provide compute capabilities.\\ +A collection of networked computers intended to provide compute capabilities. 
-\\+
 **Node**\\ **Node**\\
-One of these computers, also called host.\\ +One of these computers, also called host. 
-\\+
 **Frontend**\\ **Frontend**\\
-A special node provided to interact with the cluster via shell commands. gwdu101 ​and gwdu102 are our frontends.\\ +A special node provided to interact with the cluster via shell commands. gwdu101gwdu102 ​and gwdu103 ​are our frontends. 
-\\ + 
-**(Job-)Slot**\\ +**Task or (Job-)Slot**\\ 
-Compute capacity for one process (or "​thread"​) at a time, usually one processor core, "​core" ​for short.\\ +Compute capacity for one process (or "​thread"​) at a time, usually one processor core, or CPU for short. 
-\\+
 **Job**\\ **Job**\\
-A compute task consisting of one or several parallel processes.\\ +A compute task consisting of one or several parallel processes. 
-\\+
 **Batch System**\\ **Batch System**\\
-The management system distributing job processes across job slots. In our case Platform LSF, which is operated by shell commands on the frontends.\\ +The management system distributing job processes across job slots. In our case [[https://​slurm.schedmd.com|Slurm]], which is operated by shell commands on the frontends. 
-\\+
 **Serial job**\\ **Serial job**\\
-A job consisting of one process using one job slot.\\ +A job consisting of one process using one job slot. 
-\\+
 **SMP job**\\ **SMP job**\\
-A job with shared memory parallelization (often realized with OpenMP), meaning that all processes need access to the memory of the same node. Consequently an SMP job uses several job slots //on the same node//.\\ +A job with shared memory parallelization (often realized with OpenMP), meaning that all processes need access to the memory of the same node. Consequently an SMP job uses several job slots //on the same node//. 
-\\+
 **MPI job**\\ **MPI job**\\
-A Job with distributed memory parallelization,​ realized with MPI. Can use several job slots on several nodes and needs to be started with ''​mpirun''​ or substitute.\\ +A Job with distributed memory parallelization,​ realized with MPI. Can use several job slots on several nodes and needs to be started with ''​mpirun''​ or the Slurm substitute ​''​srun''​.
-\\ +
-**Queue**\\ +
-A label to sort jobs by general requirements and intended execution nodes.+
  
-=====  The ''​bsub''​ Command: Submitting Jobs to the Cluster ​ =====+**Partition**\\ 
 +A label to sort jobs by general requirements and intended execution nodes. Formerly called "​queue"​
  
-''​bsub''​ submits information on your job to the batch system:+=====  The ''​sbatch''​ Command: Submitting Jobs to the Cluster ​ ===== 
 + 
 +''​sbatch''​ submits information on your job to the batch system:
  
   *  What is to be done? (path to your program and required parameters)   *  What is to be done? (path to your program and required parameters)
   *  What are the requirements?​ (for example queue, process number, maximum runtime)   *  What are the requirements?​ (for example queue, process number, maximum runtime)
  
-LSF then matches the job’s requirements against the capabilities of available job slots. Once sufficient suitable job slots are found, the job is started. ​LSF considers jobs to be started in the order of their priority.+Slurm then matches the job’s requirements against the capabilities of available job slots. Once sufficient suitable job slots are found, the job is started. ​Slurm considers jobs to be started in the order of their priority. 
 + 
 +=====  Available Partitions ​ ===== 
 +We currently have two meta partitions, corresponding to broad application profiles:
  
-=====  Available Queues ​ ===== 
-We currently have two meta partitions, corresponding to broad application profiles:\\ 
 **medium**\\ **medium**\\
-This is our general purpose partition, usable for serial and SMP jobs with up to 20 tasks, but it is especially well suited for large MPI jobs. Up to 1024 cores can be used in a single MPI job, and the maximum runtime is 48 hours.\\ +This is our general purpose partition, usable for serial and SMP jobs with up to 24 tasks, but it is especially well suited for large MPI jobs. Up to 1024 cores can be used in a single MPI job, and the maximum runtime is 48 hours. 
-\\+
 **fat**\\ **fat**\\
-This is the partition for SMP jobs, especially those requiring lots of memory. Serial jobs with very high memory requirements do also belong in this partition. Up to 64 cores and 256 GB are available on one host. Maximum runtime is 48 hours.\\ +This is the partition for SMP jobs, especially those requiring lots of memory. Serial jobs with very high memory requirements do also belong in this partition. Up to 64 cores and up to 512 GB are available on one host. Maximum runtime is 48 hours.\\ 
-\\ +The nodes of the fat+ partitions ​are also present in this partition, but will only be usedif they are not needed for bigger jobs submitted to the fat+ partition.
-These are called '​meta'​ partitionsbecause ​they are just collections +
-of different partitions.\\ +
-If you need more fine grained control over the on which kind of nodes your job runs, you can also directly use the underlying '​real'​ partitions:​ +
-  * medium-fas\\ +
-test +
-  * medium-fmz +
-  * fat-fas +
-  * fat-fmz +
-  * fat+fas +
-  * fat+fmz +
-  * gpu+
  
-\\ 
-Both the "​mpi"​ and "​fat"​ queues are also available in manifestations,​ e.g. "​mpi-long",​ corresponding to special runtime requirements:​\\ 
-\\ 
-**-long**\\ 
-Here, the maximum runtime is increased to 120 hours. Job slot availability is limited, though, so expect longer waiting times.\\ 
-\\ 
-**-short**\\ 
-Here, the maximum runtime is decreased to two hours. In turn the queue has a higher base priority, but it also has limited job slot availability. That means that as long as only few jobs are submitted to the "​-short"​ queues, there will be minimal waiting times. These queues are intended for testing and development,​ not for massive production.\\ 
-\\ 
 **fat+**\\ **fat+**\\
-This queue is for jobs that require more than 256 GB RAM on single node. Nodes of fat+ queue have 512 GB, 1.5 and 2 TB RAM. Due to limited amount of such nodes, there are restrictions of using the queue, which you can find at the [[en:​services:​application_services:​high_performance_computing:​running_jobs_for_experienced_users#using_the_fat_queue|page for experienced Users]]+This partition ​is meant for very memory intensive jobs. These partitions are for jobs that require more than 512 GB RAM on single node. Nodes of fat+ partitions ​have 1.5 and 2 TB RAM. You are required ​to have specify your memory needs on job submission to use these nodes (see [[en:​services:​application_services:​high_performance_computing:​running_jobs_slurm#resource_selection|resource selection]]).\\ 
 +As general advice: Try your jobs on the smaller nodes in the fat partition first and work your way up and don't be afraid to ask for help here.
  
-=====  ''​bsub''​ Syntax and Usage  =====+**gpu** - A partition for nodes containing GPUs. Please refer to [[en:​services:​application_services:​high_performance_computing:​running_jobs_slurm#​gpu_selection]] ​
  
-<​code>​bsub <bsub options> [mpirun.lsf] <path to program> <program parameters></​code>​ +====  ​Runtime limits (QoS)  ==== 
-\\ +If the default time limits are not sufficient for your jobs, you can use a "​Quality of Service"​ or **QOS** to modify those limits on a per job basis. We currently have two QOS.
-====  ​''​bsub''​ options for serial jobs  ====+
  
-**-q <​queue>​**\\ +**long**\\ 
-Submission queue.\\ +Here, the maximum ​runtime is increased to 120 hoursJob slot availability ​is limited, though, so expect longer waiting times.
-\\ +
-**-W <​hh:​mm>​**\\ +
-Maximum ​runtime. If this time is exceeded the job is killed.\\ +
-\\ +
-**-o <​file>​**\\ +
-Store the job output in "​file"​ (otherwise it is sent by email)''​%J''​ in the filename stands for the jobid.\\+
  
-====  ''​bsub''​ options for parallel (SMP or MPI) jobs  ====+**short**\\ 
 +Here, the maximum runtime is decreased to two hours. In turn the queue has a higher base priority, but it also has limited job slot availability. That means that as long as only few jobs are submitted to the "​-short"​ queues, there will be minimal waiting times. These queues are intended for testing and development,​ not for massive production.
  
-**-<min>,<max>**\\ +=====  How to submit jobs  ===== 
-The minimum ​and maximum process countIf "​max"​ is left out, "min" ​is the exact number of job slots required.\\ + 
-\\ +Slurm supports different ways to submit jobs to the cluster: 
-**-<wrapper>**\\ +Interactively or in batch mode. We generally recommend using the 
-This option denotes a wrapper script required to run SMP or MPI jobsThe most important wrappers are ''​openmp''​ (for SMP jobs)''​intelmpi'' ​(for MPI jobs using the Intel MPI library), and ''​openmpi'' ​(for MPI jobs using the OpenMPI library).\\ +batch mode. If you need to run a job interactively,​ you can find 
-\\ +information about that in the [[en:​services:​application_services:​high_performance_computing:​running_jobs_slurm#​interactive_session_on_the_nodes|corresponding section]]. 
-**mpirun.lsf**\\ +Batch jobs are submitted to the cluster using the '​sbatch'​ command 
-LSF’s substitute for ''​mpirun''​. In MPI jobs ''​mpirun.lsf''​ needs to be put in front of the program path.\\+and a jobscript or a command:​\\ 
 +<​code>​sbatch <​options>​ [jobscript.sh | --wrap=<command>]</code>\\ 
 + 
 +**sbatch** can take a lot of options to give more information on the 
 +specifics of your job, e.g. where to run it, how long it will take 
 +and how many nodes it needsWe will examine a few of the options in 
 +the following paragraphs. For a full list of commandsrefer to the 
 +manual of the command with 'man sbatch'​. 
 + 
 +====  ​"sbatch" ​options ​ ==== 
 + 
 +**<​nowiki>​-A all</​nowiki>​**\\ 
 +Specifies the account '​all'​ for the job. This option is //​mandatory//​ for users who have access to special hardware and want to use the general partitions. 
 + 
 +**<​nowiki>​-p <​partition></​nowiki>​**\\ 
 +Specifies in which partition the job should run. Multiple partitions 
 +can be specified in a comma separated list. 
 + 
 +**<​nowiki>​--qos=<​qos></​nowiki>​**\\ 
 +Submit the job using a special QOS. 
 + 
 +**<​nowiki>​-<time></​nowiki>**\\ 
 +Maximum runtime of the jobIf this time is exceeded the job is killed. Acceptable <​time>​ formats include "​minutes"​"​minutes:​seconds",​ "​hours:​minutes:​seconds",​ "​days-hours",​ "​days-hours:​minutes"​ and "​days-hours:​minutes:​seconds" ​(example: 1-12:00:00 will request 1 day and 12 hours). 
 + 
 +**<​nowiki>​-o <​file></​nowiki>​**\\ 
 +Store the job output in "​file"​ (otherwise written to slurm-<​jobid>​)''​%J'' ​in the filename stands ​for the jobid.\\ 
 + 
 +**<​nowiki>​--noinfo</​nowiki>​**\\ 
 +Some metainformation about your job will be added to your output file. If you do not want that, you can suppress it with this flag.\\ 
 + 
 +**<​nowiki>​--mail-type=[ALL|BEGIN|END]</​nowiki>​\\ 
 +<​nowiki>​--mail-user=your@mail.com</​nowiki>​** \\ 
 +Receive mails when the jobs start, end or bothThere are even more options, refer to the sbatch man-page for more information about mail types. If you have a GWDG-mail-address,​ you do not need to specify the mail-user.\\ 
 + 
 +====  Resource Selection ​ ====
  
-====  ''​bsub'':​ Specifying process distribution with ''​-R'' ​ ====+=== CPU Selection ​===
  
-**<​nowiki>​-R span[hosts=1]</​nowiki>​**\\ +**<​nowiki>​-n <​tasks>​</​nowiki>​**\\ 
-This puts all processes on //one// hostYou always want to use this with SMP jobs.\\ +The number of tasks for this job. The default is one task per node. 
-\\ + 
-**<​nowiki>​-R span[ptile=<x>]</​nowiki>​**\\ +**<​nowiki>​-c <cpus per task><​/nowiki>​**\\ 
-''​x''​ denotes the exact number of job slots to be used on each host. If the total process ​number is not divisible by ''​x''​, the residual processes will be put on one host.\\+The number of cpus per tasksThe default is one cpu per task. 
 + 
 +**<​nowiki>​-c vs -n</​nowiki>​**\\ 
 +As a rule of thumb, if you run your code on a single node, use -c. For multi-node MPI-jobs, use -n.\\ 
 + 
 +**<​nowiki>​-<minNodes[,​maxNodes]></​nowiki>​**\\ 
 +Minimum and maximum ​number of nodes that the job should ​be executed ​on. If only one number is specifiedit is used as the precise node count.\\ 
 + 
 +**<​nowiki>​--ntasks-per-node=<​ntasks></​nowiki>​**\\ 
 +Number of tasks per node. If -n and <​nowiki>​--ntasks-per-node</​nowiki>​ is specified, this options specifies the maximum number tasks per node.
 \\ \\
-**<​nowiki>​-R span[ptile='​!'​]</​nowiki>​**\\ +=== Memory Selection === 
-**<​nowiki>​-R same[model]</​nowiki>​**\\ + 
-With this special notation, ​''​x'' ​will become the maximum number ​of cores available ​on the node type used for the jobIn other words, using '!' ​will acquire all job slots on all nodes the job runs on, provided the total number ​of job slots requested is divisible by ''​x'' ​(otherwiese ​the residual will run on one shared host).+By default, your available memory per node is the default memory per task times the number of tasks you have running on that node. You can get the default memory per task by looking at the DefMemPerCPU metric as reported by ''​scontrol show partition <​partition>​ 
 +''​ 
 + 
 +**<​nowiki>​--mem=<​size[units]></​nowiki>​**\\ 
 +Required memory per node. The Unit can be one of [K|M|G|T], but defaults to M. If your processes exceed this limit, they will be killed. 
 + 
 +**<​nowiki>​--mem-per-cpu=<​size[units]></​nowiki>​**\\ 
 +Required memory per task instead of node. <​nowiki>​--mem</​nowiki>​ and <​nowiki>​--mem-per-cpu</​nowiki>​ are mutually exclusive.\\ 
 +=== Example === 
 + 
 +''​<​nowiki>​-n 10 -N 2 --mem=5G</​nowiki>​'' ​Distributes a total of 10 tasks over 2 nodes and reserves 5G of memory ​on each node. 
 + 
 +''​<​nowiki>​--ntasks-per-node=5 -N 2 --mem=5G</​nowiki>''​ Allocates 2 nodes and puts 5 tasks on each of them. Also reserves 5G of memory on each node.  
 + 
 +''​<​nowiki>​-n 10 -N 2 --mem-per-cpu=1G</​nowiki>​'' ​Distributes a total of 10 tasks over 2 nodes and reserves 1G of memory for each task. So the memory per node depends ​on where the tasks are running.\\ 
  
 ====  The GWDG Scientific Compute Cluster ​ ==== ====  The GWDG Scientific Compute Cluster ​ ====
  
-{{ :​en:​services:​scientific_compute_cluster:​nodes.png?​1000 |}}+{{ :​en:​services:​scientific_compute_cluster:​nodes-slurm.png?1000 |}}
  
-This scheme shows the basic cluster setup at GWDG. The cluster is distributed across two facilities, with the "​ehemalige Fernmeldezentrale"​ facility hosting the older resources and the shared /scratch file system and the "​Faßberg"​ facility hosting the latest resources and the shared /scratch2 file system. The shared /​scratch2 ​is usually the best choice ​for temporary data in your jobs, but it is only available at the Faßberg resources (selectable ​with ''​-scratch2''​). The scheme also shows the queues and resources by which nodes are selected using the ''​-q''​ and ''​-R''​ options of ''​bsub''​.+This scheme shows the basic cluster setup at GWDG. The cluster is distributed across two facilities, with the "​ehemalige Fernmeldezentrale"​ facility hosting the older resources and the shared /scratch file system and the "​Faßberg"​ facility hosting the latest resources and the shared /scratch2 file system. The shared ​/scratch and /​scratch2 ​are usually the best choices ​for temporary data in your jobs, but /scratch is only available at the "​Fernmeldezentrale"​ (fmz) resources (select ​it with ''​-C scratch''​) and /​scratch2 ​is only available at the Faßberg ​(fas) resources (select it with ''​-scratch2''​). The scheme also shows the queues and resources by which nodes are selected using the ''​-p'' ​(partition) ​and ''​-C'' ​(constraint) ​options of ''​sbatch''​.
  
-====  ''​bsub'':​ Specifying node properties with ''​-R'' ​ ====+====  ''​sbatch'':​ Specifying node properties with ''​-C'' ​ ==== 
 + 
 +**-C scratch[2]**\\ 
 +The node must have access to shared ''/​scratch''​ or ''/​scratch2''​. 
 + 
 +**-C fmz / -C fas**\\ 
 +The node has to be at that location. It is pretty similar to -C scratch / -C scratch2, since the nodes in the FMZ have access to scratch and those at the Fassberg location have access to  scratch2. This is mainly for easy compatibility with our old partition naming scheme. 
 + 
 +**-C [architecture]**\\ 
 +request a specific CPU architecture. Available Options are: abu-dhabi, ivy-bridge, haswell, broadwell. See [[en:​services:​application_services:​high_performance_computing:​start#​hardware_overview|this table]] for the corresponding nodes.
  
-**-R scratch[2]**\\ 
-The node must have access to shared ''/​scratch''​ or ''/​scratch2''​.\\ 
-\\ 
-**-R work**\\ 
-The node must have access to one of the shared ''/​work''​ directories.\\ 
-\\ 
-**-R "​ncpus=<​x>"​**\\ 
-Choose only nodes with a job slot count of ''​x''​. This is useful with ''<​nowiki>​span[ptile=<​x>​]</​nowiki>''​.\\ 
-\\ 
-**-R big**\\ 
-Choose the nodes with the maximum memory per core available in the queue. Currently only distinguishes ''​gwdaxxx''​ from ''​gwdpxxx''​ nodes.\\ 
-\\ 
-**-R latest**\\ 
-Always use the latest (and usually most powerful) nodes available in the queue. To get a list of current latest nodes run the command ''​bhosts -R latest''​ on one of the frontends. You can also check the [[en:​services:​application_services:​high_performance_computing:​new_nodes|Latest Nodes]] page for more information. 
  
-====  ​''​bsub'': ​Using Job Scripts ​ ====+====  Using Job Scripts ​ ====
  
-A job script is a shell script with a special comment section: In each line beginning with ''#​BSUB''​ the following text is interpreted as a ''​bsub''​ option. Here is an example:+A job script is a shell script with a special comment section: In each line beginning with ''#​SBATCH''​ the following text is interpreted as a ''​sbatch''​ option. These options have to be at the top of the script before any other commands are executed. Here is an example:
  
 <​code>​ <​code>​
-#!/bin/sh +#!/bin/bash 
-#BSUB -q mpi +#SBATCH ​-p medium 
-#BSUB -W 00:10 +#SBATCH ​-10:00 
-#BSUB -o out.%J+#SBATCH ​-o outfile-%J
  
 /​bin/​hostname /​bin/​hostname
Line 152: Line 180:
  
 <​code>​ <​code>​
-bsub < <script name>  ​+sbatch ​<script name>  ​
 </​code>​ </​code>​
 \\ \\
Line 159: Line 187:
 An exclusive job does use all of its allocated nodes exclusively,​ i.e., it never shares a node with another job. This is useful if you require all of a node's memory (but not all of its CPU cores), or for SMP/MPI hybrid jobs, for example. An exclusive job does use all of its allocated nodes exclusively,​ i.e., it never shares a node with another job. This is useful if you require all of a node's memory (but not all of its CPU cores), or for SMP/MPI hybrid jobs, for example.
  
-To submit an exclusive job add ''​-x''​ to your bsub options. For example, to submit a single task job, which uses a complete fat node with 256 GB memory, you could use:+Do not combine ''<​nowiki>​--exclusive</​nowiki>''​ and ''<​nowiki>​--mem=<​x></​nowiki>''​. In that case you will get all available tasks on the node, but your memory will still be limited to what you specified with ''<​nowiki>​--mem</​nowiki>''​ 
 + 
 +To submit an exclusive job add ''​<​nowiki>​--exclusive</​nowiki>​''​ to your sbatch ​options. For example, to submit a single task job, which uses a complete fat node, you could use:
 <​code>​ <​code>​
-bsub --fat -R big ./mytask+sbatch ​--exclusive -p fat -t 12:00:00 --wrap="​./mytask"
 </​code>​ </​code>​
-(-R big requests ​256 GB node, excluding the 128 GB nodes in the fat queue)+This allocates either ​complete gwda nodes with 256GB, or a complete dfa node with 512GB.
  
 For submitting an OpenMP/MPI hybrid job with a total of 8 MPI processes, spread evenly across 2 nodes, use: For submitting an OpenMP/MPI hybrid job with a total of 8 MPI processes, spread evenly across 2 nodes, use:
 <​code>​ <​code>​
 export OMP_NUM_THREADS=4 export OMP_NUM_THREADS=4
-bsub --q mpi -n 8 -R span[ptile=4-a intelmpi ​mpirun.lsf ./​hybrid_job+sbatch ​--exclusive ​-p medium ​-N 2 --ntasks-per-node=4 --wrap="​mpirun ./​hybrid_job"
 </​code>​ </​code>​
 (each MPI process creates 4 OpenMP threads in this case). (each MPI process creates 4 OpenMP threads in this case).
  
-Please note that fairshare evaluation and accounting is done based on the number of job slots **allocated**. So the first example would count as 64 slots for both fairshare and accounting. 
- 
-Using exclusive jobs does not require reserving all of a node's slots explicitly (e.g., with span[ptile='​!'​]) and subsequently using the MPI library'​s mpiexec or mpiexec.hydra to set the process number, as we explain in our introductory course. This makes submitting a hybrid job as exclusive job more straightforward. 
- 
-However, there is a disadvantage:​ LSF will not reserve the additional job slots required to get a node exclusively. Therefore, when the cluster is very busy, an exclusive job needing a lot of nodes may wait significantly longer. 
- 
-====  A Note On Job Memory Usage  ==== 
- 
-LSF will try to fill up each node with processes up to its job slot limit. Therefore each process in your job must not use more memory than available //per core//! If your per core memory requirements are too high, you have to add more job slots in order to allow your job to use the memory of these slots as well. If your job's memory usage increases with the number of processes, you have to leave additional job slots //empty//, i.e., do not run processes on them. 
- 
-====  Recipe: Reserving Memory for OpenMP ​ ==== 
- 
-The following job script recipe demonstrates using empty job slots for reserving memory for OpenMP jobs: 
- 
-<​code>#​!/​bin/​sh 
-#BSUB -q fat 
-#BSUB -W 00:10 
-#BSUB -o out.%J 
-#BSUB -n 64 
-#BSUB -R big 
-#BSUB -R "​span[hosts=1]"​ 
- 
-export OMP_NUM_THREADS=8 
-./​myopenmpprog 
-</​code>​ 
-\\ 
 ====  Disk Space Options ​ ==== ====  Disk Space Options ​ ====
  
Line 204: Line 208:
 **/​local**\\ **/​local**\\
 This is the local hard disk of the node. It is a fast - and in the case of the ''​gwda,​ gwdd, dfa, dge, dmp, dsu''​ and ''​dte''​ nodes even very fast, SSD based - option for storing temporary data. There is automatic file deletion for the local disks.\\ This is the local hard disk of the node. It is a fast - and in the case of the ''​gwda,​ gwdd, dfa, dge, dmp, dsu''​ and ''​dte''​ nodes even very fast, SSD based - option for storing temporary data. There is automatic file deletion for the local disks.\\
-\\+A directory is automatically created for each job at ''/​local/​jobs/<​jobID>''​ and the path is exported as the environment variable ''​$TMP_LOCAL''​. 
 **/​scratch**\\ **/​scratch**\\
-This is the shared scratch space, available on ''​gwda''​ and ''​gwdd''​ nodes and frontends ''​gwdu101''​ and ''​gwdu102''​. You can use ''​-scratch''​ to make sure to get a node with access to shared /scratch. It is very fast, there is no automatic file deletion, but also no backup! We may have to delete files manually when we run out of space. You will receive a warning before this happens.\\ +This is the shared scratch space, available on ''​gwda''​ and ''​gwdd''​ nodes and frontends ''​gwdu101''​ and ''​gwdu102''​. You can use ''​-scratch''​ to make sure to get a node with access to shared /scratch. It is very fast, there is no automatic file deletion, but also no backup! We may have to delete files manually when we run out of space. You will receive a warning before this happens. 
-\\+
 **/​scratch2**\\ **/​scratch2**\\
-This space is the same as scratch described above except it is **ONLY** available on the nodes ''​dfa,​ dge, dmp, dsu''​ and ''​dte''​ and on the frontend ''​gwdu103''​. You can use ''​-scratch2''​ to make sure to get a node with access to that space.\\ +This space is the same as scratch described above except it is **ONLY** available on the nodes ''​dfa,​ dge, dmp, dsu''​ and ''​dte''​ and on the frontend ''​gwdu103''​. You can use ''​-scratch2''​ to make sure to get a node with access to that space. 
-\\+
 **$HOME**\\ **$HOME**\\
 Your home directory is available everywhere, permanent, and comes with backup. Your attributed disk space can be increased. It is comparably slow, however. Your home directory is available everywhere, permanent, and comes with backup. Your attributed disk space can be increased. It is comparably slow, however.
Line 219: Line 224:
  
 <​code>​ <​code>​
-#!/bin/sh +#!/bin/bash 
-#BSUB -fat +#SBATCH ​-fat 
-#BSUB -n 64 +#SBATCH ​-N 1 
-#BSUB -R "​span[hosts=1]"​ +#SBATCH ​-n 64 
-#BSUB -scratch +#SBATCH ​-scratch 
-#BSUB -W 24:00 +#SBATCH ​-t 1-00:00:00
-#BSUB -C 0 +
-#BSUB -a openmp+
  
 export g09root="/​usr/​product/​gaussian"​ export g09root="/​usr/​product/​gaussian"​
Line 246: Line 249:
 If you use scratch space only for storing temporary data, and do not need to access data stored previously, you can request /scratch or /scratch2: If you use scratch space only for storing temporary data, and do not need to access data stored previously, you can request /scratch or /scratch2:
 <​code>​ <​code>​
-#BSUB -"​scratch||scratch2"​+#SBATCH ​-"​scratch|scratch2"​
 </​code>​ </​code>​
 For that case ''/​scratch2''​ is linked to ''/​scratch''​ on the latest nodes. You can just use ''/​scratch/​${USERID}''​ for the temporary data (don't forget to create it on ''/​scratch2''​). On the latest nodes data will then be stored in ''/​scratch2''​ via the mentioned symlink. For that case ''/​scratch2''​ is linked to ''/​scratch''​ on the latest nodes. You can just use ''/​scratch/​${USERID}''​ for the temporary data (don't forget to create it on ''/​scratch2''​). On the latest nodes data will then be stored in ''/​scratch2''​ via the mentioned symlink.
  
-=====  Miscallaneous LSF Commands ​ =====+==== Interactive session on the nodes ====
  
-While ''​bsub''​ is arguably ​the most important LSF commandyou may also find the following commands useful:+As stated before, ​''​sbatch''​ is used to submit jobs to the clusterbut there is also ''​srun''​ command wich can be used to execute a task directly on the allocated nodes. That command is helpful to start interactive session on the node. You can use interactive session to avoid running large tests on the frontend (a good idea!) you can get an interactive session (with the bash shell) on one of the ''​medium''​ nodes with
  
-**bjobs**\\ +<​code>​srun ​--pty -p medium ​-N 1 -c 16 /bin/bash</code>
-Lists current jobs. Useful options are: ''​-p, -l, -a, , <​jobid>, ​-u all, -q <​queue>, ​-<host>''​.\\+
 \\ \\
-**bhist**\\ +''​<​nowiki>​--pty</nowiki>'' ​requests support for an interactive shell, and ''​-p medium'' ​the corresponding partition. ''​-c 16'' ​ensures that you 16 cpus on the nodeYou will get a shell prompt, as soon as a suitable node becomes availableSingle thread, non-interactive jobs can be run with 
-Lists older jobs. Useful options are: ''​-l, -n, <jobid>''​.\\ +<code>srun -p medium ​./​myexecutable</​code>​
-\\ +
-**lsload**\\ +
-Status of cluster nodes. Useful options are: ''​-l, <​hostname>​''​.\\ +
-\\ +
-**bqueues**\\ +
-Status of batch queues. Useful options are: ''​-l, <​queue>​''​.\\ +
-\\ +
-**bhpart**\\ +
-Why do I have to wait? ''​bhpart''​ shows current user prioritiesUseful options are: ''​-r, <host partition>''​.\\ +
-\\ +
-**bkill**\\ +
-The Final Command. It has two use modes:+
  
-  -  ''​bkill <​jobid>'':​ This kills a job with a specific jobid. +==== GPU selection ​====
-  -  ''​bkill <selection ​options> 0'':​ This kills all jobs fitting the selection options. Useful selection options are: ''​-q <​queue>,​ -m <​host>''​.+
  
-Have a look at the respective man pages of these commands to learn more about them! +In order to use GPU you should submit ​your job to the ''​gpu'' ​partition, and request GPU count and optionally the modelCPUs of the nodes in gpu partition ​are evenly distributed ​for every GPUSo if you are requesting ​a single ​GPU on the node with 20 cores and 4 GPUs, you can get up to 5 cores reserved exclusively ​for you, the same is with memorySo for example, ​if you want 2 GPUs of model Nvidia GeForce GTX 1080 with 10 CPUsyou can submit ​a job script ​with the following ​flags:
- +
-=====  Getting Help  ===== +
-The following sections show you where you can get status Information and where you can get support in case of problems. +
-====  Information sources ​ ==== +
- +
-  *  Cluster status page +
-    *  [[http://​lsf.gwdg.de/​lsfinfo/​]] +
-  *  HPC announce mailing list +
-    *  [[https://​listserv.gwdg.de/​mailman/​listinfo/​hpc-announce]] +
- +
-====  Using the GWDG Support Ticket System ​ ==== +
- +
-Write an email to <​hpc@gwdg.de>​. ​In the body: +
-  *  State that your question is related ​to the batch system. +
-  *  State your user id (''​$USER''​). +
-  *  If you have problem with your jobs please //always send the complete standard output and error//! +
-  *  If you have a lot of failed jobs send at least two outputs. You can also list the jobids of all failed jobs to help us even more with understanding ​your problem. +
-  *  If you don’t mind us looking at your files, please state this in your request. You can limit your permission ​to specific directories or files. +
- +
-====== Running Jobs (for experienced Users) ====== +
- +
-Job scheduling on the scientific compute cluster is handled by IBM LSF. In most cases this means that only few changes to your current job scripts and ''​bsub'' ​command lines are necessary, if you have used LSF before. There are three different node types in the cluster, each being served by one or more queues of the general form ''<​nodetype>​[-<​category>​]''​. For example, ''​fat''​ type nodes are served by the ''​fat''​ queue for normal jobs, and by ''​fat-long''​ for long jobs. +
- +
-===== Nodes' specification ===== +
- +
-**Currently there are next "​mpi"​ nodes:** +
-  * 168 nodes with 20 Intel Ivy-Bridge CPU cores +
-  * 101 nodes with 24 Intel Broadwell CPU cores +
-  * 72 nodes with 16 Intel Haswell CPU cores +
-  * 32 nodes with 24 Intel Haswell CPU cores +
-Broadwell nodes have 128 GB of memory, Ivy- and Sandy-Bridge nodes 64 GB and Haswell nodes 128/256 GB. +
- +
-**Current "​fat"​ nodes:** +
-  * 5 nodes with 48 AMD CPU cores (with 128 GB of memory) +
-  * 25 nodes with 64 AMD CPU cores (with 256 GB of memory) +
-  * 15 nodes with 24 Intel Broadwell CPU cores (with 512 GB of memory) +
-  * 5 nodes with 40 Intel Haswell CPU cores (with 1.5 TB of memory) +
-  * 1 node with 32 Intel Haswell CPU cores (with 2 TB of memory) +
- +
-**There are "gpu" nodes as well:** +
-  * 20 nodes with 1 NVidia GTX 770 GPUs +
-  * 15 nodes with 2 NVidia GTX 980 GPUs +
-  * 10 nodes with 2 NVidia K40 GPUs +
-GTX nodes are for single precision CUDA applications and K40 nodes for double precision or memory intensive CUDA applications. +
- +
-The ''​mpi''​ nodes provide the bulk of the compute power of our compute cluster and are meant for all types of applications. They are especially well suited for large MPI jobs, as they have a balanced compute to network performance ratio. The ''​fat''​ nodes are meant for shared memory parallelized workloads scaling beyond 16 cores, and for all applications requiring more than 64 GB of memory on a single ​node. +
- +
-===== Interactive session ​on the nodes ===== +
- +
-As stated before, ''​bsub''​ is used to submit jobs to the cluster. For example, to avoid running large tests on the frontend (a good idea!) you can get an interactive session (with the bash shell) on one of the ''​mpi''​ nodes with +
- +
-<​code>​ +
-bsub -ISs -q mpi-short -n 16 -R '​span[hosts=1]'​ -R np16 /​bin/​bash</​code>​ +
-\\ +
-''​-ISs''​ requests support for an interactive shell, ​and ''​-q mpi-short''​ the corresponding queue. ''​-n 16 -R <​nowiki>'​span[hosts=1]'</​nowiki>​ -R np16''​ ensures that you get a Sandy-Bridge (16 core, ''​np16''​) node exclusively (see below, use ''​-n 64''​ for tp and fat queues). You will get a shell prompt, as soon as a suitable node becomes available. Single thread, non-interactive jobs can be submitted with +
- +
-<​code>​ +
-bsub -q mpi ./​myexecutable</​code>​ +
- +
-===== MPI jobs ===== +
- +
-Note that a single thread job submitted like above will share its execution host with other jobs. It is therefore expected that it does not use more than the memory available per core! On the ''​mpi''​ nodes this amount is GB, as well as on the newer ''​fat''​ nodes. If your job requires more, you must assign additional cores. For example, if your single thread job requires 64 GB of memory, you must submit it like this: +
- +
-<​code>​ +
-bsub -q mpi -n 16 ./​myexecutable</​code>​ +
-\\ +
-OpenMPI jobs can be submitted as follows: +
- +
-<​code>​ +
-bsub -q mpi -n 256 -a openmpi mpirun.lsf ./​myexecutable</​code>​ +
-\\ +
-For Intel MPI jobs it suffices ​to use ''​-a intelmpi''​ instead of ''​-a openmpi''​. Please note that LSF will not load the correct modules (compiler, library, MPI) for you. You either have to do that before executing ''​bsub''​in which case your setup will be copied to the execution hosts, or you will have to use a job script and load the required modules there.  +
- +
-A new feature in LSF is ''​pinning''​ support. ''​Pinning''​ (in its most basic version) means instructing the operating system to not apply its standard scheduling algorithms to your workloads, but instead keep processes on the CPU core they have been started onThis may significantly improve performance ​for some jobs, especially on the ''​fat''​ nodes with their high CPU core count. ''​Pinning''​ is managed via the MPI library, and currently only OpenMPI is supported. There is not much experience with this feature, so we are interested in your feedback. Here is an example+
- +
-<​code>​ +
-bsub -R "​select[np16] span[ptile=16] affinity[core(1):​cpubind=core]"​ -q mpi -n 256 -a openmpi mpirun.lsf ./​myexecutable</​code>​ +
-\\ +
-The affinity string ''"​affinity[core(1):​cpubind=core]"''​ means that each task is using one core and that the binding should be done based on cores (as opposed to socketsNUMA units, etc). Because this example is for a pure MPI application,​ x in ''​core(x)''​ is one. In an SMP/MPI hybrid job, x would be equal to the number ​of threads per task (e. g.equal to ''​OMP_NUM_THREADS''​ for Openmp/MPI hybrid jobs). +
- +
-===== SMP jobs ===== +
- +
-Shared memory parallelized jobs can be submitted with +
- +
-<​code>​ +
-bsub -q mpi -n 8,20 -R '​span[hosts=1]'​ -openmp ./​myexecutable</​code>​ +
-\\ +
-The ''​span''​ option is required, without it, LSF will assign cores to the job from several nodes, if that is advantageous from the scheduling perspective. +
- +
-===== Using the fat+ queue ===== +
- +
-Nodes with a lot of memory are very expensive and should not normally be used for jobs which could also run on our other nodes. Therefore, please note the following ​policies: +
- +
-  * Your job must need more than 250 GB RAM. +
-  * Your job must use at least a full 512 GB node or half a 1.5 TB or 2 TB node: +
- +
-  * For a full 512 GB node:+
 <​code>​ <​code>​
-#BSUB -x +#SBATCH ​-p gpu 
-#BSUB -R "​maxmem < 600000"​+#SBATCH ​-n 10 
 +#SBATCH -G gtx1080:2
 </​code>​ </​code>​
  
-  * For half a 1.5 TB node (your job needs more than 500 GB RAM): 
-<​code>​ 
-#BSUB -n 20 
-#BSUB -R span[hosts=1] 
-#BSUB -R "​maxmem < 1600000 && maxmem > 600000"​ 
-</​code>​ 
  
-  * For a full 1.5 TB node (your job needs more than 700 GB RAM): +You can also omit the model selection, here is an example of selecting ​GPU of any available model:<​code>​ 
-<​code>​ +#SBATCH ​-p gpu 
-#BSUB -x +#SBATCH ​-n 10 
-#BSUB -R "​maxmem < 1600000 && maxmem > 600000"​+#SBATCH -G 1
 </​code>​ </​code>​
  
-  * For half a 2 TB node (your job needs more than 700 GB RAM): +There are different options to select the number of GPUs, such as ''​%%--gpus-per-node%%'',​ ''​%%--gpus-per-task%%''​ and more. See the [[https://​slurm.schedmd.com/​sbatch.html|sbatch man page]] for details.
-<​code>​ +
-#BSUB -n 16 +
-#BSUB -R span[hosts=1] +
-#BSUB -R "​maxmem > 1600000"​ +
-</code>+
  
-  * For a full 2 TB node (your job needs more than 1.5 TB RAM): +Currently we have several generations of NVidia GPUs in the cluster, ​namely:
-<​code>​ +
-#BSUB -x +
-#BSUB -R "​maxmem > 1600000"​ +
-</​code>​ +
- +
-The 512 GB nodes are also available ​in the fat queue, without these restrictions. However, fat jobs on these nodes have a lower priority compared to fat+ jobs. +
- +
-===== CPU architecture selection ===== +
- +
-Our cluster ​provides four generations of Intel CPUs and two generations of AMD CPUs. Howeverthe main difference between these CPU types is whether they support Intel'​s AVX2 or not. For selecting this we have introduced the x64inlvl (for x64 instruction level) label:+
  
 <​code>​ <​code>​
-x64inlvl=1 ​Supports only AVX +gtx1080 ​GeForce GTX 1080  
-x64inlvl=2 ​Supports AVX and AVX2+gtx980  ​GeForce GTX 980 
 +k40     : Nvidia Tesla k40
 </​code>​ </​code>​
  
-In order to choose an AVX2 capable node you therefore have to include+Most GPUs are commodity graphics cards, and only provide good performance for single precision calculations. If you need double precision performance,​ or error correcting memory (ECC RAM), you can select the Tesla GPUs with
 <​code>​ <​code>​
-#BSUB -R "​x64inlvl=2"+#SBATCH ​-p gpu 
 +#SBATCH -G k40:2
 </​code>​ </​code>​
-in your submission script.+Our Tesla K40 are of the Kepler generation.
  
-If you need to be more specificyou can also directly choose the CPU generation:+<​code>​ sinfo -p gpu --format=%N,%G </​code>​ shows a list of host with GPUs, as well as their type and count.
  
-<​code>​ +=====  Miscellaneous Slurm Commands ​ =====
-amd=1 : Interlagos +
-amd=2 : Abu Dhabi+
  
-intel=1 ​Sandy Bridge +While ''​sbatch''​ is arguably the most important Slurm command, you may also find the following commands useful:
-intel=2 : Ivy Bridge +
-intel=3 : Haswell +
-intel=4 : Broadwell +
-</​code>​+
  
-So, in order to choose any AMD CPU: +**<nowiki>sinfo</nowiki>**\\ 
-<code> +Shows current status ​of the cluster and queues
-#BSUB -R amd +
-</code+
-In order to choose an Intel CPU of at least Haswell generation:​ +
-<​code>​ +
-#BSUB -R "​intel>​=3"​ +
-</​code>​ +
-This is equivalent to ''​x64inlvl=2''​.+
  
-===== GPU selection =====+**<​nowiki>​squeue</​nowiki>​**\\ 
 +Lists current jobs (default: all users). Useful options are: ''<​nowiki>​-u $USER, -p <​partition>,​ -j <​jobid></​nowiki>''​.
  
-In order to use a GPU you should submit your job to the ''​gpu''​ queue, and request GPU shares. Each node equipped with a GPU provides as many GPU shares as it has cores, independent of how many GPUs are built in. So for example, on the nodes, which have 24 CPU cores, the following would give you exclusive access to GPUs: +**<​nowiki>​scontrol show job <jobid></nowiki>**\\ 
-<code> +Full job informationOnly available while job is running ​and short time thereafter
-#BSUB -R "​rusage[ngpus_shared=24]"​ +
-</code+
-Note that you need not necessarily also request 24 cores with ''​-n 24'',​ as jobs from the MPI queue may utilize free CPU cores if you do not need themThe latest "​gpu"​ nodes have two GPUs each, and you should use both, if possible.+
  
-If you request less shares than cores available, other jobs may also utilize the GPUsHowever, we have currently no mechanism to select ​specific one for a job. This would have to be handled in the application or your job script.+**<​nowiki>​squeue --start -j <​jobid></​nowiki>​**\\ 
 +Expected start timeThis is rough estimate.
  
-A good way to use the nodes which have 2 GPUs with jobs only working ​on one GPU would be to put two together ​in one job script and preselect ​GPU for each one.+**<​nowiki>​sacct -j <​jobid>​ --format=JobID,​User,​UID,​JobName,​MaxRSS,​Elapsed,​Timelimit</​nowiki>​**\\ 
 +Get job Information even after the job has finished.\\ 
 +**Note ​on ''​sacct'':​** Depending on the parameters given ''​sacct''​ chooses a time window ​in a rather unintuitive way. This is documented in the DEFAULT TIME WINDOW section of its man page. If you unexpectedly get no results from your ''​sacct''​ query, try specifying the start time with, e.g. ''<​nowiki>​-S 2019-01-01</​nowiki>''​.\\ 
 +The ''<​nowiki>​--format</​nowiki>''​ option knows many more fields like **Partition**,​ **Start**, **End** or **State**, ​for the full list refer to the man page.
  
-Currently we have several generations of NVidia GPUs in the cluster, selectable ​in the same way as CPU generations:​+**<​nowiki>​scancel</​nowiki>​**\\ 
 +Cancels jobs. Examples:​\\ 
 +''<​nowiki>​scancel 1235</​nowiki>''​ - Send the termination Signal (SIGTERM) to job 1235\\ 
 +''<​nowiki>​scancel --signal=KILL 1235</​nowiki>''​ - Send the kill Signal (SIGKILL) to job 1235\\ 
 +''<​nowiki>​scancel --state=PENDING --user=$USER --partition=medium-fmz</​nowiki>''​ - Cancel all your pending jobs in partition ''<​nowiki>​medium-fmz</​nowiki>''​
  
-<​code>​ +Have a look at the respective man pages of these commands to learn more about them!
-nvgen=1 : Kepler +
-nvgen=2 : Maxwell +
-nvgen=3 : Pascal +
-</​code>​+
  
-Most GPUs are commodity graphics cards, and only provide good performance for single precision calculations. If you need double precision performance,​ or error correcting memory (ECC RAM), you can select the Tesla GPUs with +====== LSF to Slurm Conversion Guide ====== 
-<​code>​ +This is a short guide on how to convert ​the most common options in your jobscripts from LSF to Slurm.
-#BSUB -R tesla +
-</​code>​ +
-Our Tesla K40 are of the Kepler generation (nvgen=1).+
  
-If you want to make sure to run on a node equipped with two GPUs use+^ Description ​                    ^ LSF                    ^ Slurm                         ^ Comment ​                                                                                                                                                                                      ^ 
-<code+| Submit job                      | bsub < job.sh ​         | sbatch job.sh ​                | No < in Slurm! ​                                                                                                                                                                               | 
-#BSUB -R "ngpus=2+| Scheduler Comment in Jobscript ​ | #BSUB -...             | #SBATCH -...                  |                                                                                                                                                                                               | 
-</code>+| Queue/​Partition ​                | -q <​queue> ​            | -p <​partition> ​               |                                                                                                                                                                                               | 
 +| Walltime ​                       | -W 48:00               | -t 2-00:​00:​00 ​                | -t 48:00 means 48 min.                                                                                                                                                                        | 
 +| Job Name                        | -J <name             | -J <​name> ​                    ​| ​                                                                                                                                                                                              | 
 +| Stdout ​                         | -o <​outfile> ​          | -o <​outfile> ​                 | %J substituted for JobID                                                                                                                                                                      | 
 +| Stderr ​                         | -e <​errfile> ​          | -e <​errfile> ​                 | %J substituted for JobID                                                                                                                                                                      | 
 +#Jobslots ​                      | -n #                   | -n #                          |                                                                                                                                                                                               | 
 +| One Host                        | -R "span[hosts=1]" ​    | -N 1                          |                                                                                                                                                                                               | 
 +| Process Distribution ​           | -R "​span[ptile=<x>]" ​  | %%--ntasks-per-node x%%       ​| ​                                                                                                                                                                                              | 
 +| Exclusive Node                  | -x                     | %%--exclusive%% ​              ​| ​                                                                                                                                                                                              | 
 +| Scratch ​                        | -R scratch[2] ​         | -C "​scratch[2]" ​              ​| ​                                                                                                                                                                                              | 
 +^ Queue -> Partition Conversion ​                                                                                                                                                                                                                                                        ​|||| 
 +| General Purpose ​                | -q mpi                 | -p medium ​                    ​| ​                                                                                                                                                                                              | 
 +|                                 | -q mpi-short ​          | -p medium %%--qos=short%% ​    ​| ​                                                                                                                                                                                              | 
 +|                                 | -q mpi-long ​           | -p medium %%--qos=long%% ​     |                                                                                                                                                                                               | 
 +|                                 | -q fat                 | -p fat                        |                                                                                                                                                                                               | 
 +|                                 | -q fat-short ​          | %%-p fat --qos=short%% ​       |                                                                                                                                                                                               | 
 +|                                 | -q fat-long ​           | %%-p fat --qos=long%% ​        ​| ​                                                                                                                                                                                              | 
 +|                                 | -ISs -q int /​bin/​bash ​ | -p int -n 20 -N 1 --pty bash  | Don't forget -n 20 -N 1, otherwise, you will only get access to a single core. Fore more Detail See [[en:​services:​application_services:​high_performance_computing:​interactive_queue:​|here]]. ​ |
  
-===== Memory selection ​=====+=====  ​Getting Help  ​===== 
 +The following sections show you where you can get status Information and where you can get support in case of problems. 
 +====  Information sources  ​====
  
-Note that the following paragraph is about **selecting** nodes with enough memory for a jobThe mechanism to actually **reserve** that memory does not change: The memory you are allowed to use equals memory per core times slots (-n option) requested.+  ​ HPC announce mailing list 
 +    ​ ​[[https://​listserv.gwdg.de/​mailman/​listinfo/​hpc-announce]]
  
-You can select a node either by currently available memory (mem) or by maximum available memory (maxmem). If you request complete nodes, ​the difference is actually very small, as a free node's available memory is close to its maximum memory. All requests are in MB.+====  Using the GWDG Support Ticket System ​ ====
  
-To select a node with more than about 500 GB available memory use: +Write an email to <hpc@gwdg.de>. In the body: 
-<code+  ​* ​ State that your question is related to the batch system. 
-#BSUB -R "​mem>​500000"​ +  ​* ​ State your user id (''​$USER''​). 
-</​code>​ +  ​* ​ If you have problem ​with your jobs please ​//always send the complete standard output and error//! 
-To select ​node with more than about 6 GB maximum memory per core use: +  ​* ​ If you have a lot of failed jobs send at least two outputs. You can also list the jobids of all failed jobs to help us even more with understanding your problem. 
-<​code>​ +  *  If you don’t mind us looking at your files, please state this in your request. You can limit your permission to specific directories or files.
-#BSUB -R "​maxmem/ncpus>​6000"​ +
-</code> +
-(Yes, you can do basic math in the requirement string!)+
  
-It bears repeatingNone of the above is a memory reservation. If you actually want to reserve "​mem"​ memory, the easiest way is to combine ''​-R "​mem>​...''​ with ''​-x''​ for an exclusive job.+[[KategorieScientific Computing]]
  
-Finally, note that the ''​-M''​ option just denotes the memory limit of your job per core (in KB). This is of no real consequence,​ as we do not enforce these limits and it has no influence on the host selection. 
- 
- 
-Besides the options shown in this article, you can of course use the options for controlling walltime limits (-W), output (-o), and your other requirements as usual. You can also continue to use job scripts instead of the command line (with the ''#​BSUB <​option>​ <​value>''​ syntax). 
- 
-Please consult the LSF man pages if you need further information. 
- 
-[[Kategorie:​ Scientific Computing]]