|
Program newAD2 is a tool for nonlinear regression (fitting) of physical quantities. Number 2 in the name represents version of the program (first version, newAD wasn't numbered). The name newAD2 is used in two ways –
both for the whole package of programs and for the command that launches the text console (frontend) used to control it (see the
newAD2 section below); the intended meaning should always be clear from the context.
Program is distributed by pvm into several processes, enabling parallelization on single computers or also on heterogeneous computer clusters.
In the past, the heterogeneous cluster consisted of various UNIX-compatible machines; later this was narrowed down to machines running different Linux distributions only.
Nowadays, within the heterogeneous cluster we only make use of the possibility to optimize the code for individual computing nodes according to the processor type.
Processes running on the main computer only:
- masterAD2 Main process ensuring communication between other child processes.
- newAD2 Text console enabling interactive control and scripting.
- newAD2gui Graphical user interface for interactive control.
- watcherAD2 Main process supervising cluster function. More specifically, it ensures that the necessary programs are running on each computer (node) and it deals with problems related to disconnecting and reconnecting of nodes or with crashes of slave computers during calculation.
- spawnerAD2 Process ensuring calculation distribution among nodes.
- addhosterAD2, spiritAD2 and heartAD2 Auxiliary processes for proper cluster operation.
- restorerAD2 Process providing restart of the calculation in case of a crash of the whole system, i.e. of the main computer.
- importerAD2 Process enabling to load current system operation from out or log files.
- librarianAD2 Process enabling data storage and download from the main computer.
Processes running on all nodes, i.e. on both main and slave computers:
- inspectorAD2 Process monitoring workload on nodes and ensuring their dynamical configuration.
- slaveAD2 Process which contains implemented physical models. In a fact, process full name is slaveAD2-OTF, where OTF (Optics of Thin Films) extension is name of only yet implemented model for optics of thin films. This allows to implement different physical models in future, which would then have different extension. Moreover, slaveAD2 can have another extension, which distinguishes between individual clusters (see system installation for more users). Usually more of these processes run on a single node — one for each processor core, or for each thread if the processor supports hyperthreading.
The program's text and graphical frontends are described on separate pages: