. The boot schema from which LAM is started can be provided to XMPI so that it may be presented as an inventory of nodes on which programs may be run.
The state information
is obtained from one or two sources, a running application started by XMPI
or a file containing trace data from a traced MPI application. When XMPI
is started, its top-level overview window is blank. Once an application
is started or a trace file is loaded, the overview window fills with a
tiled group of hexagons, each representing the state of one MPI process.
Application Overview: processes and messages at a glance
A traffic light symbol indicates wether the process is
running or blocked. No traffic light is shown for processes which have
either finalized or not yet initialized the MPI library.
A process window
with full MPI details on a single process and its unreceived messages is
popped up by a mouse click on an interesting cell in the application overview.
Several process windows may be on the screen simultaneously so that the
user can focus on problem interactions between a few processes. When monitoring
a running application the camera "Snap" button or "Snapshot" item in the
"Application" menu updates the state information on all processes at any
Process Focus: details on process status and its unreceived messages
The datatype button
displays the type map.
The next button shows the next group of identical messages.
The group button highlights the members of the communicator's process group.
process is blocked, the function name, peer process rank, communicator,
message tag and element count are displayed. If unreceived messages are
available, their quantity, source process rank, communicator, message tag
and element count are displayed. By leaving a few process windows on the
screen, a user can focus debugging on a small and manageable colection
of misbehaving processes.
Communication Timeline: Placing the dial gives a full snapshot of MPI details.
The "Clean" button or "Clean" item in the "Application" menu terminates an application and the development cycle can be repeated. The previous application can be rerun with the "Rerun" button or "Rerun" item in the "Application" menu.