[[Image(OmpSs2_logo_full.png)]]

= Programming with OmpSs-2 =

* Introduction 
* Quick User Guide


== Introduction ==
OmpSs-2 is a programming model composed of a set of directives and library routines that can be used in conjunction with a high-level programming language in order to develop concurrent applications. Its name originally comes from two other programming models: **OpenMP** and **StarSs**. The design principles of these two programming models constitute the fundamental ideas used to conceive the OmpSs philosophy.

[[Image(pools.png, 20%)]]

OmpSs-2 **thread-pool** execution model differs from the **fork-join** parallelism implemented in OpenMP.



== File Systems ==
On the DEEP-EST system, three different groups of filesystems are available:

 * the [http://www.fz-juelich.de/ias/jsc/EN/Expertise/Datamanagement/OnlineStorage/JUST/Filesystems/JUST_filesystems_node.html JSC GPFS filesystems], provided via [http://www.fz-juelich.de/ias/jsc/EN/Expertise/Datamanagement/OnlineStorage/JUST/JUST_node.html JUST] and mounted on all JSC systems;

 * the DEEP-EST (and SDV) parallel BeeGFS filesystems, available on all the nodes of the DEEP-EST system;

 * the filesystems local to each node.

The users home folders are placed on the shared GPFS filesystems.  With the advent of the new user model at JSC ([http://www.fz-juelich.de/ias/jsc/EN/Expertise/Supercomputers/NewUsageModel/NewUsageModel_node.html JUMO]), the shared filesystems are structured as follows:

 * $HOME: each JSC user has a folder under `/p/home/jusers/`, in which different home folders are available, one per system he/she has access to.  These home folders have a low space quota and are reserved for configuration files, ssh keys, etc.

 * $PROJECT: In JUMO, data and computational resources are assigned to projects: users can request access to a project and use the resources associated to it. As a consequence, each user has a folder within each of the projects he/she is part of. For the DEEP project, such folder is located under `/p/project/cdeep/`. Here is where the user should place data, and where the old files generated in the home folder before the JUMO transition can be found.

The DEEP-EST system doesn't mount the $SCRATCH and $ARCHIVE filesystems, as it is expected to provide similar functionalities with its own parallel filesystems.

The following table summarizes the characteristics of the file systems available in the DEEP-EST and DEEP-ER (SDV) systems:


== Stripe Pattern Details ==
It is possible to query this information from the deep login node, for instance:

{{{
manzano@deep $ fhgfs-ctl --getentryinfo /work/manzano
Path: /manzano
Mount: /work
EntryID: 1D-53BA4FF8-3BD3
Metadata node: deep-fs02 [ID: 15315]
Stripe pattern details:
+ Type: RAID0
+ Chunksize: 512K
+ Number of storage targets: desired: 4

manzano@deep $ beegfs-ctl --getentryinfo /sdv-work/manzano
Path: /manzano
Mount: /sdv-work
EntryID: 0-565C499C-1
Metadata node: deeper-fs01 [ID: 1]
Stripe pattern details:
+ Type: RAID0
+ Chunksize: 512K
+ Number of storage targets: desired: 4
}}}
Or like this:

{{{
manzano@deep $ stat -f /work/manzano
  File: "/work/manzano"
    ID: 0        Namelen: 255     Type: fhgfs
Block size: 524288     Fundamental block size: 524288
Blocks: Total: 120178676  Free: 65045470   Available: 65045470
Inodes: Total: 0          Free: 0

manzano@deep $ stat -f /sdv-work/manzano
  File: "/sdv-work/manzano"
    ID: 0        Namelen: 255     Type: fhgfs
Block size: 524288     Fundamental block size: 524288
Blocks: Total: 120154793  Free: 110378947  Available: 110378947
Inodes: Total: 0          Free: 0
}}}
See http://www.beegfs.com/wiki/Striping for more information.

== Additional infos ==
Detailed information on the '''BeeGFS Configuration''' can be found [https://trac.version.fz-juelich.de/deep-er/wiki/BeeGFS here].

Detailed information on the '''BeeOND Configuration''' can be found [https://trac.version.fz-juelich.de/deep-er/wiki/BeeOND here].

Detailed information on the '''Storage Configuration''' can be found [https://trac.version.fz-juelich.de/deep-er/wiki/local_storage here].

Detailed information on the '''Storage Performance''' can be found [https://trac.version.fz-juelich.de/deep-er/wiki/SDV_AdminGuide/3_Benchmarks here].

== Notes ==
 * The /work file system which is available in the DEEP-EST prototype, is as well reachable from the nodes in the SDV (including KNLs and KNMs) but through a slower connection of 1 Gig. The file system is therefore not suitable for benchmarking or I/O task intensive jobs from those nodes

 * Performance tests (IOR and mdtest) reports are available in the BSCW under DEEP-ER -> Work Packages (WPs) -> WP4 -> T4.5 - Performance measurement and evaluation of I/O software -> Jülich DEEP Cluster -> Benchmarking reports: https://bscw.zam.kfa-juelich.de/bscw/bscw.cgi/1382059

 * Test results and parameters used stored in JUBE:

{{{
user@deep $ cd /usr/local/deep-er/sdv-benchmarks/synthetic/ior
user@deep $ jube2 result benchmarks

user@deep $ cd /usr/local/deep-er/sdv-benchmarks/synthetic/mdtest
user@deep $ jube2 result benchmarks
}}}