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The Result's cache mechanism allows the analysis and visualization of lots of results which, otherwise, could not be held entirely in memory.
Instead of loading all results from the file(s), a certain amount of memory, a memory pool, is reserved and used to load and unload the result values as they are needed.
When this mechanism is enabled, with the indexed options enabled, and a result's file is opened for the first time, GiD verifies the correctness of the file and gets some information about the results, such as minimum and maximum values, amount of memory needed, position in file; and this information is stored in the index file. The next time the same result's file is opened, only the index file is loaded, reducing the load time considerably. But no results are loaded, they are loaded only on-demand.
If the indexed options are off, then no index file is created or read, and so the parsing of the result's file is perfumed performed each time is it's opened, but no results is loaded in memory. They are loaded on demand.
If a result is selected to do, for instance, a contour fill visualization and their values are not in memory, then GiD checks if there is enough space in the memory pool and loads them. If their values are already in memory, the time-stamp of the result is actualized.
If there is not enough space in the memory pool to load the desired result, then the oldest results are unloaded, and their memory freed, until there is enough memory to load the desired result.
What's cached: Only results which are already stored in files are cached, i.e. files read with Files --> Open, Open multiple or Merge.
What's not cached: When cuts, extrusions are done or isosurfaces are converted to full featured meshes, the generated results are held in memory. Results created in GiD using the Window --> Create result, Create statistical result are held in memory. Also results imported using Files --> Import or using the plug-in mechanism or the TCL procedure GiD_Result create ... are held in memory too.
In order to cache these results, save the model, with Files --> Export --> Post information --> whole model / HDF5 GiD post and open it again.
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