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Disk usage: Rename section and update
Using the option '''-j x''' (where x is the number of your CPU-Cores you wish to assign to the job) will speed up the whole compilation process considerably.
== Disk usage and build time ==Having both Keeping compiled programprograms, source code, and data from git repositories requires some hard disk space: It it will take something like 13 12 GB of spacefor just [[SimGear]], FlightGear and [[FGData]] (i.e., the SIMGEAR, FGFS and DATA components)With an Intel Core i7 860 CPU (2.80 GHz) purchased in 2009, compiling [[SimGear]] and FlightGear 2019.2 with option <code>-j8</code> takes about 14 minutes. If you don't have a fast machineand build using only one core, it will may require several hours of compilation time.
== Optimus technology ==
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