bspprof(1)

NAME
bspprof - The Oxford BSP Toolset communication profiler for BSPlib

SYNOPSIS
bspprof [input-file] [output-file] [command-line-options]

DESCRIPTION
The Oxford BSP toolset communication profiler analyses trace files generated during the execution of a BSPlib program. The profiler converts trace files into PostScript (level 2) documents that are suitable for visualisation on a wide variety of graphical devices. Trace files are generated by adding the option -prof when compiling BSPlib programs with bspfront(1) .

The profiler produces three types of PostScript graphs as output:

1)  Strata-graphs for either the number of distinct communications that occur over time, or the number of bytes communicated. Two graphs are presented per profile:

    a)  the number of bytes (or communications) going in to a processor.

    b)  the number of bytes (or communications) going out from a processor.

2)  Prediction graphs that are similar to 1) except that the lower graph shows the predicted cost of the communication on the machine the profiler was run on. If the -arch command is used to specify another architecture, then that architectures BSP parameters will be used instead. Alternatively, the BSP parameters of the architecture which the prediction is for can be entered using the -slg option.

3)  A G graph, which is also based upon 1) except the bottom graph shows the effect of g over time. For a true BSP machine, g should be constant.

OPTIONS
Options must be separate: `-dr ' is quite different from `-d -r '. Here is a summary of all the options, grouped by type. Explanations can be found in the appropriate sections below:

Overall Options
    -title string -zoom from,to -colo[u]r -letter -bytes -packets -ignore -outline

Strata Graph Options
    -comm

Prediction Graph Options
    -predict -slg s,l,g,[nhalf] -arch string -nhalfmodel -hgmodel -bisselingmodel

G Graph
    -ggraph -ceilingg integer -hrelgl

OVERALL OPTIONS

-t string
    Use string as the title of the profile.

-zoom from,to
    Zoom in on the section of the profile between times (in seconds) from and to . If a superstep stradles either from or to it is ignored.

-colo[u]r
    Use coloured bars when producing the profile in preference to the default grey-scale hashing.

-letter
    Generate a postscript file that will print on American letter format paper. The default print area is A4.

-bytes
    Displays the number of bytes transferred from each process during each superstep.

-packets
    Displays the number of distinct messages from each process during each superstep.

-ignore file
    Don't profile any supersteps from the file string.

-outline
    Only show the accumulated message sizes for a superstep. This option is useful to see the general shape of the profile without generating large postscript files.

STRATA GRAPH OPTIONS

-comm
    Produce a strata-graph showing two graphs with the amounts of data entering and exiting each processor for each superstep over time.

PREDICTION GRAPH OPTIONS

-predict
    Produce a graph that contrasts the experimental results with a prediction based upon the BSP cost model.

-slg s,l,g[,nhalf]
    When generating the prediction profile, the options to -slg are numbers which represent the BSP parameters:

    s   is the Megaflop/s rating for the machine.

    l   the minimum number of flops for a barrier synchronisation.

    g   the asymptotic number of flops required for all processors to communicate a single 32bit word to another process.

    nhalf
        the number of words required for the communication performance to deteriorate to 2g.
See bspparam(1) for information concerning the BSP parameter database.

-arch string
    Specifies that the program was run on architecture string ; where string is one of the valid architecture options that is returned from bsparch -help .

-hgmodel
    The formula h.g is used as the cost of communicating a h-relation.

-nhalfmodel
    The formula h.g.(nhalf/h +1) is used as the cost of communicating a h-relation. i.e., messages smaller than nhalf are attributed a larger cost to take into effect communication startup costs. This is the most accurate, and therefore the default cost model used in the profiler.

-bisselingmodel
    The formula h.g.nhalf is used as the cost of communicating a h-relation. This will give an upper bound, pessimistic cost of communication.

G GRAPH

-ggraph
    For each superstep, assume that l is fixed, and plot a graph for the variance of g realised for the superstep. Although the BSP model assumes a fixed g, this option is useful when trying to visualise the effects of contention in the implementation; or alternatively to check if a machine is truly scalable!

-ceilingg number
    Specify the maximum value of g to show in the lower G graph. This option is useful when useful when trying to scale multiple graphs to the same ranges.

-hrelgl
    In the ggraph, we assume that l is constant, and we plot the variance of g. When the size of the h-relation is much smaller than l/g, then a small variance at runtime in l will produce a large variance in g. By default, when generating the profile for the G graph, h-relations smaller than l/g are ignored. With this option, they are plotted as small white dots.

FILES
The file ROOTDIR/include/bsp_parameters.ascii contains the BSP parameters for various platforms; where ROOTDIR is usually set in the top level Makefile of the BSPlib source.

SEE ALSO
bsplib(3), bspfront(1), bsparch(1) ``The theory, practice, and a tool for BSP performance prediction'' Jonathan Hill, Paul Crumpton, and David Burgess. In EuroPar'96. LNCS, Springer-Verlag, August 1996. See:
ftp://ftp.comlab.ox.ac.uk/pub/Documents/techpapers/Jonathan.Hill/HillCrumptonBurgess_europar96.ps.Z The Oxford BSP toolset web pages can be found at:
http://www.bsp-worldwide.org/implmnts/oxtool/

BUGS
Problems and bug reports should be mailed to bsplib-bugs@comlab.ox.ac.uk

COPYING
Copyright 1995,1996,1997 University of Oxford

Permission to use, copy, modify, and distribute this software, and to incorporate it, in whole or in part, into other software, is hereby granted without fee, provided that:

i   the above copyright notice and this permission notice appear in all copies of the source code, and the above copyright notice appear in clearly visible form on all supporting documentation and distribution media;

ii
     modified versions of this software be accompanied by a complete change history describing author, date, and modifications made;

iii
     and any redistribution of the software, in original or modified form, be without fee and subject to these same conditions.

AUTHORS
Jonathan.Hill@comlab.ox.ac.uk

http://www.comlab.ox.ac.uk/oucl/people/jonathan.hill.html