QDP++

The QDP++ interface provides a data-parallel programming environment suitable for Lattice QCD where operations in operator/infix form can be applied on lattice wide objects. The interface provides a level of abstraction such that high-level user code written above the interface can be run unchanged on a single processor workstation or a collection of multiprocessor nodes with parallel communications. Architectural dependencies are hidden below the interface. A variety of types for the site elements are provided. To achieve good performance, overlapping communication and computation primitives are provided.

News

9/12/07 As of QDP++ 1.25.0 we have moved to using compiler intrinsics for SSE. This has several benefits:

• The code now builds with gcc 4.x series of compilers
• The code now builds with the Intel Compiler

• There is an expected performance drop from using function calls.
• GCC3.4 our trusted and loved compiler, no longer works. Update to GCC4

Getting QDP++

The latest version of QDP++ is qdp++-1.25.1. This is recommended for most systems, except for 32 bit intel SSE based systems.

For 32 bit intel SSE based systems we recommend sticking with qdp++-1.24.6

Source Code

The source for the current version of qdp++ is qdp++-1.25.1.tar.gz - here

The source for the version 1.24.6 of qdp++ (32 bit i386 targets only) is qdp++-1.24.6.tar.gz - here

Tarball versions of previous releases can be found in the release directory here

Direct source code access instructions via CVS are here.

What? No RPMS?

As it turned out the packaging of RPMs is not really as straightforward to automate as we'd like. Also there are issues with availability of shared libraries on some systems. Therefore we have currently suspended the rolling of RPM distributions.

Dependencies

In order to build QDP++ you will need

• to have the libxml2 development library installed. If you don't have this, and don't have a package for your OS, you can build it from this copy of the source or you can try downloading it from The LibXML web page On a QCDOC a hacked version is needed, the source for which is here. On Linux and Cygwin Systems there is a package for libxml2. On RedHat systems it is called "libxml2-devel".
• if you want to work on a parallel machine, you will need to have the QMP Message Passing Harness installed. The current version of the source for QMP is qmp-2.1.6.tar.gz.
• if you want to work on the BlueGene or the QCDOC you may want some of the optimizations from bagel_qdp-1.1.7.tar.gz. For this you will also need the BAGEL assembler generator package from Peter Boyle and agree to all his requests on his web page.

Documentation and User Information

Here is the current pdf version of the manual, and there is also an html version. There are implementation snapshots available along with documentation produced by doxygen which can be found in the doc subdirectory. A user guide is also available.

The tutorial is a very simple application using QDP++.

The demonstration shows a more sophisticated application using QDP++.

Developer Information

Recent news about software releases are available. There is a text and an html version of the ChangeLog available.

There is also a software snapshot of the CVS head revision, and there are also some CVS statistics

The motivation for this development comes from the U.S. Dept. of Energy SciDAC program. See the USQCD home pages for more details.

The USQCD Software home page lists other relevant packages including QMP.