HI,Ramprasad , thank you for your reply very much!
Maybe you misunderstand my issue.
My omx program is omx progam with a single process. All capture，dei, encode, decode and display components are builded and used in the single process. I create two pthreads in the single process, one for processing encoder ,another for processing decoder. when the two pthreads work simultaneously, the omx program will hang after a piece of time, such as serveral minutes or half an hour. the time is related with MC_HDVPSS_INT_HEAP_CACHED and MC_HDVICP2_INT_HEAP_CACHED. I don't know why the omx program will hang after some time!