Return to Statistics_Cache.tex CVS log

Up to [LON-CAPA] / loncom / html / adm / help / tex

Annotation of loncom/html/adm/help/tex/Statistics_Cache.tex, revision 1.3

1.1       matthew     1: \label{Statistics_Cache}
                      2: 
                      3: The \textbf{\index{Statistics Cache}Statistics Cache} manages the data 
                      4: used in computing student performance statistics.
                      5: 
                      6: Much of the time spent computing statistics is actually used to
1.3     ! webbsuza    7: compile student data into a more useful format; the temporary course
        !             8: cache.  Normally student data is maintained in an archived format,
1.1       matthew     9: which does not provide for rapid access.  Since each student's data is
                     10: stored on their home server in their account, and not with the course,
                     11: it takes time to compile the data and store it in the temporary course
                     12: cache.  All of the statistics modes use the same cache so the process
                     13: of compiling the student data does not need to be repeated when
                     14: successive statistics are requested.
                     15: 
                     16: Only those students who are involved in the current calculation will
                     17: have their data compiled.  When you modify the selected set of
                     18: students, by changing the section you are computing statistics with,
                     19: the caches will be updated.
                     20: 
                     21: The temporary course cache is maintained for 2 days on the server used
                     22: for the statistics computation.
                     23: 
                     24: The cache management buttons, marked \textbf{Clear Caches} and
                     25: \textbf{Update Caches}, appear when the temporary course caches are in
1.2       matthew    26: use.  
                     27: 
                     28: \textbf{Clear Caches} causes the entire cache for the course to
1.1       matthew    29: be flushed, discarding all the current contents.  The cache is then
                     30: rebuilt to display the desired statistics.  The normal use of
                     31: statistics should not require you to press this button, but it is here
                     32: for completeness.
                     33: 
1.3     ! webbsuza   34: \textbf{Update Caches} checks the students' records for updates since when their 
        !            35: data was compiled.  Any changes to the students' record for your
1.1       matthew    36: course will be reflected after this button has been pressed.  The
                     37: \textbf{Update Caches} button is useful if your students are currently
1.3     ! webbsuza   38: completing a homework set, and you wish to evaluate their progress in
        !            39: the timeframe your statistics were generated.
1.1       matthew    40: