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CVS tags: version_2_9_X, version_2_9_99_0, version_2_9_1, version_2_9_0, version_2_8_X, version_2_8_99_1, version_2_8_99_0, version_2_8_2, version_2_8_1, version_2_8_0, version_2_7_X, version_2_7_99_1, version_2_7_99_0, version_2_7_1, version_2_7_0, version_2_6_X, version_2_6_99_1, version_2_6_99_0, version_2_6_3, version_2_6_2, version_2_6_1, version_2_6_0, version_2_5_X, version_2_5_99_1, version_2_5_99_0, version_2_5_2, version_2_5_1, version_2_5_0, version_2_4_X, version_2_4_99_0, version_2_4_2, version_2_4_1, version_2_4_0, version_2_3_X, version_2_3_99_0, version_2_3_2, version_2_3_1, version_2_3_0, version_2_2_X, version_2_2_99_1, version_2_2_99_0, version_2_2_2, version_2_2_1, version_2_2_0, version_2_1_X, version_2_1_99_3, version_2_1_99_2, version_2_1_99_1, version_2_1_99_0, version_2_1_3, version_2_1_2, version_2_1_1, version_2_1_0, version_2_12_X, version_2_11_X, version_2_11_5, version_2_11_4_uiuc, version_2_11_4_msu, version_2_11_4, version_2_11_3_uiuc, version_2_11_3_msu, version_2_11_3, version_2_11_2_uiuc, version_2_11_2_msu, version_2_11_2_educog, version_2_11_2, version_2_11_1, version_2_11_0_RC3, version_2_11_0_RC2, version_2_11_0_RC1, version_2_11_0, version_2_10_X, version_2_10_1, version_2_10_0_RC2, version_2_10_0_RC1, version_2_10_0, version_2_0_X, version_2_0_99_1, version_2_0_2, version_2_0_1, version_2_0_0, version_1_99_3, version_1_99_2, version_1_99_1_tmcc, version_1_99_1, version_1_99_0_tmcc, version_1_99_0, version_1_3_X, version_1_3_3, version_1_3_2, version_1_3_1, version_1_3_0, version_1_2_X, version_1_2_99_1, version_1_2_99_0, version_1_2_1, version_1_2_0, version_1_1_X, version_1_1_99_5, version_1_1_99_4, version_1_1_99_3, version_1_1_99_2, version_1_1_99_1, version_1_1_99_0, version_1_1_3, version_1_1_2, version_1_1_1, version_1_1_0, version_1_0_99_3, version_1_0_99_2, version_1_0_99_1, version_1_0_99, version_1_0_3, version_1_0_2, version_1_0_1, version_1_0_0, version_0_99_5, version_0_99_4, loncapaMITrelate_1, language_hyphenation_merge, language_hyphenation, bz6209-base, bz6209, bz5969, bz2851, PRINT_INCOMPLETE_base, PRINT_INCOMPLETE, HEAD, GCI_3, GCI_2, GCI_1, BZ5971-printing-apage, BZ5434-fox, BZ4492-merge, BZ4492-feature_horizontal_radioresponse
Help on caching to avoid confusion.

    1: \label{Caching}
    2: LON-CAPA does not serve static web pages, but generates pages and other 
    3: resources dynamically and adaptively based on a large number of data input
    4: sources, such as the user preference, the course environment, maps, etc.
    5: 
    6: Since LON-CAPA also has to sustain large workloads, it is 
    7: prohibitive to gather, compile, and process these data for every single
    8: access, when in the vast majority of cases, nothing has changed between the
    9: current and previous requests.
   10: 
   11: LON-CAPA thus caches data. There are basically two different 
   12: \textbf{caching mechanisms\index{caching mechanisms}}, which LON-CAPA uses:
   13: 
   14: \begin{itemize}
   15: \item Caching at \textbf{course initialization\index{course initialization}}:
   16: Several sources of data are compiled when a user enters a course during a 
   17: session. An example is the table of contents (DOCS/NAV) for the course - 
   18: if you change DOCS, you need
   19: to re-enter (``\textbf{re-initialize}'') the course in order to see the 
   20: effects.
   21: 
   22: The course environment (PARM/Course Environment) in general also only gets 
   23: evaluated when entering a course, and while it does get re-evaluated for your
   24: session whenever you change anything, it - like DOCS changes - will not 
   25: immediately take effect for
   26: other users currently working in the course. So if for example you disable
   27: course discussion, users will only be prevented from discussion when they 
   28: enter the course the next time. 
   29: 
   30: \item Caching of \textbf{assessment parameters\index{assessment parameters}}:
   31: Data such as the deadline of homework problems, and the text of Simple 
   32: Problems, is only re-read \textbf{every ten minutes}. It can thus happen that
   33: you open up a homework problem in PARM, but for another ten minutes, some 
   34: students cannot access it. Also changes to Simple Problems will not immediately
   35: take effect for all users (including yourself).
   36: \end{itemize}
   37:  
   38: It is important to be aware of these mechanisms, since otherwise results can
   39: be confusing (``Didn't I just change this???'').
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