| "track","process","thread","thread_process","ts","dur","category","name","arg_set_id" | |
| "[NULL]","[NULL]","t1","[NULL]",10000,1000,"cat","event1",0 | |
| "[NULL]","[NULL]","t1","[NULL]",20000,8000,"cat","event2",0 | |
| "[NULL]","[NULL]","t1","[NULL]",21000,7000,"[NULL]","atrace",0 |