OBE LEB Performance and Usage


Oct 16, 1997

   At yesterday's meeting the point was brought up that in certain
cases we are becoming LEB processing time limited rather than 
Telemetry limited.  To address this issue I have compiled a table
of buffer usage and LEB usage stats per telescope.  These values were
generated from what was loaded with the Planning Tool.  LEB time
consists of camera setup, mech movements, exposure time, read out,
and image compression time.  We tend to over-estimate the LEB time
in the Planning Tool so the actual times on board are probably
about ~10-20% less.
 
-SP
 
 
 
Submode  kbps
  2      26.7
  3       7.0
  4       5.3
  5       7.9   'the nominal rate'
  6      15.8
 
 
Date Plan Loaded  Submode             total    C1      C2      C3      EIT
 
97 Oct 01           5      Buffer    101.1%    24.6%   22.8%   17.4%   35.2%
                           LEB Time   89.3%    36.5%   18.7%   14.2%   30.6%
 
97 Oct 02           5      Buffer    101.5%    26.0%   20.7%   17.7%   35.6%
                           LEB Time   92.4%    37.8%   17.0%   15.1%   30.2%
 
97 Oct 03           5      Buffer     99.6%    26.6%   19.9%   17.7%   35.8%
                           LEB Time   92.3%    38.0%   17.6%   14.7%   29.6%
 
97 Oct 04-05        5      Buffer     99.7%    26.0%   19.9%   18.0%   36.1%
                           LEB Time   92.3%    37.3%   17.6%   15.1%   30.0%
 
97 Oct 06           5      Buffer     97.9%    20.4%   17.1%   13.9%   48.5%
                           LEB Time   92.0%    28.4%   14.3%   11.8%   45.5%
 
97 Oct 07           5      Buffer    100.5%    23.1%   19.4%   13.9%   43.6%
                           LEB Time   94.2%    32.2%   16.9%   11.8%   39.1%
 
97 Oct 08           6      Buffer     55.1%    21.7%   22.4%   15.5%   40.4%
                           LEB Time   98.2%    32.0%   18.1%   12.0%   37.9%
 
97 Oct 09           6      Buffer     59.1%    24.3%   22.7%   16.2%   36.8%
                           LEB Time  108.2%    35.8%   18.7%   11.9%   33.5%
 
97 Oct 10           3      Buffer     99.7%    24.7%   17.0%   13.0%   45.3%
                           LEB Time   85.2%    34.0%   16.0%   11.4%   38.7%
 
97 Oct 12           3      Buffer    100.2%    26.4%   16.6%   12.3%   44.7%
                           LEB Time   88.1%    35.8%   15.9%   11.0%   37.2%
 
97 Oct 14           3      Buffer     99.0%    25.8%   16.5%   13.1%   44.6%
                           LEB Time   83.8%    36.4%   16.5%   11.6%   35.5%
 
97 Oct 15           3      Buffer    108.7%    23.2%   16.0%   11.7%   49.1%
                           LEB Time   86.0%    35.3%   15.3%   10.6%   38.8%

Note: the low Buffer usage on Oct 8-9 was due to the unexpected submode 6 TM.  The
LASCO planners were unable to generate a plan in time to take advantage of the
extra TM.