Compile with multiple processors.
Specify the -xjobs option to set how many processes the compiler creates to complete its work. This option can reduce the build time on a multi-cpu machine. In this release of the f95 compiler, -xjobs works only with the -xipo option. When you specify -xjobs=n, the interprocedural optimizer uses n as the maximum number of code generator instances it can invoke to compile different files.
Generally, a safe value for n is 1.5 multiplied by the number of available virtual processors. Using a value that is many times the number of available virtual processors can degrade performance because of context switching overheads among spawned jobs. Also, using a very high number can exhaust the limits of system resources such as swap space.
You must always specify -xjobs with a value. Otherwise an error diagnostic is issued and compilation aborts.
Multiple instances of -xjobs on the command line override each other until the rightmost instance is reached.
The following example compiles more quickly on a system with two processors than the same command without the -xjobs option.
example% f95 -xipo -xO4 -xjobs=3 t1.f t2.f t3.f |