embedded linux - mlock usage in RAM only system -


we have time-critical process (third party code) , has mlockall. porting code our embedded system doesnt have hard disk. ram system, boots sd card , has storage in sd card.

does mlockall has performance benefits @ in ram system?

just check whether there swap partition tried: cat /proc/swaps filename type size used priority

in case can remove mlockall not going add value in our system. kindly help.

when under memory pressure linux kernel might decide evict pages ram. dirty pages (containing writeable data) can swapped out. clean pages (read only) text section of process might dropped. such pages brought in via page fault when needed.

the first case can not happen there no swap. second case might happen , prevented via mlockall call.

overall discussion theoretical running system under memory pressure introduces lot of non deterministic behaviour bad real time system.


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