sets the concurrency level of the threading system of the java virtual machine jvm to the specified level . the concurrency level specifies how many threads can run in parallel on different cpus at any given time for jvm implementations that use posix threads with pthread_scope_process scheduling scope . a concurrency level of 0 means that the operating system will automatically adjust the concurrency level depending on the number of threads blocking on system calls , but this will probably not exploit more than one cpu in multiporocessor machines . if the concurrency level if set to more than the number of available processors in the machine the performance might degrade . for jvm implementations that use posix threads with pthread_scope_system scheduling scope or jvm implementations that use windows r threads and maybe others , setting the concurrency level has no effect . in this cases the number of cpus that can be exploited by the jvm is not limited in principle , all cpus are available to the jvm . for jvm implementations that use `` green '' threads setting the concurrency level , and thus calling this method , makes no sense , since `` green '' threads are all contained in one user process and can not use multiple cpus . in fact calling this method can result in a jvm crash is the shared library shlib_name has been compiled to use posix threads . concode_field_sep int LIB_STATE_NOT_LOADED concode_elem_sep int LIB_STATE_LOADED concode_elem_sep int libState concode_elem_sep int LIB_STATE_NOT_FOUND concode_elem_sep String SHLIB_NAME concode_field_sep boolean loadLibrary concode_elem_sep int getThreadConcurrencyN concode_elem_sep int getThreadConcurrency concode_elem_sep void checkLibrary concode_elem_sep void setThreadConcurrencyN
void function ( int arg0 ) { checkLibrary ( ) ; if ( arg0 < 0 ) throw new IllegalArgumentException ( ) ; setThreadConcurrencyN ( arg0 ) ; }