The onstat -g ath option prints information about all threads.
IBM Informix Dynamic Server Version 10.00.UC1 -- On-Line -- Up 18:47:42 -- 101376 Kbytes Threads: tid tcb rstcb prty status vp-class #scheds name *2 b3132d8 0 2 running 2adm 0 adminthd 3 b313650 0 2 sleeping forever 3cpu 0 childthd *5 b4c4028 0 4 sleeping secs: 0 1cpu 9960 Cosvr 6 b4de2d0 0 2 sleeping secs: 1 3cpu 2014 dfm_svc *7 b4de640 0 4 sleeping forever 1cpu 91469 xmf_svc ... *49 c58a450 b3b13a8 4 sleeping secs: 1 1cpu 2014 onmode_mon
1511 c8277c8 b3b1a68 3 cond wait netnorm 5cpu 0 onbar_2 1512 c85b378 b3b2128 2 sleeping forever 5cpu 0 x_exec_1.61 1515 c5f14f0 b3b27e8 2 sleeping forever 1cpu 0 llbu_2