NAME

     memsrt  -  module  to  output  sorted  traces  using  memory
     storage

SYNOPSIS

     memsrt [ -Nntap ] [ -Ootap ] [ -ntable ] [ -eiend ] [  -lnst
     ] [ -mnend ] [ -bibuf ] [ -G ] [ -S ] [ -D ] [ -R ] [ -X ] [
     -orig ] [ -V ] [ -? ]

DESCRIPTION

     memsrt generates sorted traces from the input data  set  and
     the  appropriate  entries  from  the sort table.  It's func-
     tionality and command line arguments are exactly the same as
     sisort.  The differences are only internal:  memsrt utilizes
     internal memory to store the input data.  The presort  table
     is  read  and the largest internal memory buffer possible is
     calculated.  The input data is  read  in  chunks  into  this
     buffer  and the sort is done on each chunk in memory.  There
     may be performance improvement on the cray -  especially  if
     your  data  reside  on the slow XFS directories -  since the
     data are read from disk into the buffer memory  using  large
     buffers  and  therefore  a  minimum  of  system  interrupts.
     sisort accesses  the  data  directly  from  disk  in  random
     sequence and hence cannot use large buffers greatly increas-
     ing system interrupts.  The user should see  little  benefit
     on the suns.

     memsrt gets both its data and its  parameters  from  command
     line  arguments.  These arguments specify the input, output,
     end time, sort table, sort type, renumber option,  and  ver-
     bose printout, if desired.

     Note:  if you need to do common offset sorting and you  can-
     not  fit  ALL your data into memory at one time you must use
     sisort

     Note:  if you are piping in you must be able to fit  ALL  of
     the  data  into memory at one time.  Otherwise you will have
     to first write the data to a disk  file  then  pick  up  the
     input data using the -N[] memsrt command line entry

  Command line arguments
     -N ntap
          Enter the input data set name or file immediately after
          typing  -N   You  can only pipe data into memsrt if all
          the data can be read  into  memory.   This  input  file
          should  include  the  complete  path  name  if the file
          resides in a different directory.  Example -N/vsp/dummy
          tells the program to look for file 'dummy' in directory
          'vsp'


     -O otap
          Enter the output data  set  name  or  file  immediately
          after typing -O.  This output file is not required when
          piping the output to another process.  The output  data
          set also requires the full path name (see above).

     -n table
          Enter the name of the sort table generated by presort.

     -e iend
          Enter the end time of the output traces in ms  (default
          = last sample)

     -l nst
          Enter the start index to be output, i.e. if  -D  option
          (cdp sort) was specified then nst will be the first cdp
          output  (default = first index)

     -m nend
          Enter the last index to be output  (default =  last  on
          input)

     -G -S -D -R -X
           -G causes common receiver sorted traces to be  output;
          the output record numbers are set to the GI index.
           -S causes common source sorted traces  to  be  output;
          the output record numbers are set to the source index.
           -D causes common depth sorted traces to be output; the
          output record numbers are set to the CDP index.
           -R causes common offset sorted traces  to  be  output;
          the  output records are padded with zero traces to com-
          mon receiver sort size
           -X causes common offset sorted traces  to  be  output;
          the output record are not padded
           NOTE: use only one of the above flags
           NOTE: in the case of arbitrary sort words  in  presort
          the  three  sort  indices are accessed in the order -G,
          -S, -D

     -orig
          Include on command line if out traces and  records  are
          to  retain  their original numbers in positions 107 and
          106 of the trace header.

     -b ibuf
          Enter the alternate  memory  buffer  size  (in  words).
          Defaults:   on  the  Suns, 1MW (megaword); on the cray,
          128MW.  Increasing this can sometimes enable you to fit
          an  entire  data  set  into  memory with the bonuses of
          being able to pipe into memsrt and limiting  disk  I/O.
          However, one should keep in mind that all machines have
          a memory limit (512 MW on the cray) and that this  will
          result in an ungracious crash.

     -V   Enter the command line argument '-V' to get  additional
          printout.

     -?   Enter this (or '-?' if you are running in  c-shell)  to
          get  online  help.   The  program  will terminate after
          printing this.

SEE ALSO

     sisort, disort, presort, presortc, compsort, postsort

COPYRIGHT

     copyright 2001, Amoco Production Company
               All Rights Reserved
          an affiliate of BP America Inc.