Monitor threads with onstat -g ath output
Use the onstat -g ath command to view a list of all threads. Unlike the onstat –u command, this list includes internal daemon threads that do not have a database server task-control block.
The onstat -g ath command display does not include the session ID (because not all threads belong to sessions).
The status
field contains information
on the status of thread, such as running
, cond
wait
, IO Idle
, IO Idle
, sleeping
secs:
number_of_seconds
, or sleeping
forever
. The following output example identifies many threads
as sleeping forever
. To improve performance, you
can remove or reduce the number of threads that are identified as sleeping
forever
.
Threads:
tid tcb rstcb prty status vp-class name
2 10bbf36a8 0 2 sleeping forever 3lio lio vp 0
3 10bc12218 0 2 sleeping forever 4pio pio vp 0
4 10bc31218 0 2 sleeping forever 5aio aio vp 0
5 10bc50218 0 2 sleeping forever 6msc msc vp 0
6 10bc7f218 0 2 sleeping forever 7aio aio vp 1
7 10bc9e540 10b231028 4 sleeping secs: 1 1cpu main_loop()
8 10bc12548 0 2 running 1cpu tlitcppoll
9 10bc317f0 0 3 sleeping forever 1cpu tlitcplst
10 10bc50438 10b231780 2 sleeping forever 1cpu flush_sub(0)
11 10bc7f740 0 2 sleeping forever 8aio aio vp 2
12 10bc7fa00 0 2 sleeping forever 9aio aio vp 3
13 10bd56218 0 2 sleeping forever 10aio aio vp 4
14 10bd75218 0 2 sleeping forever 11aio aio vp 5
15 10bd94548 10b231ed8 3 sleeping forever 1cpu aslogflush
16 10bc7fd00 10b232630 1 sleeping secs: 26 1cpu btscanner 0
32 10c738ad8 10b233c38 4 sleeping secs: 1 1cpu onmode_mon
50 10c0db710 10b232d88 2 cond wait netnorm 1cpu sqlexec
Threads that a primary decision-support thread started have a name that indicates their role in the decision-support query. The following figure shows four scan threads that belong to a decision-support thread.
Threads:
tid tcb rstcb prty status vp-class name
11 994060 0 4 sleeping(Forever) 1cpu kaio
12 994394 80f2a4 2 sleeping(secs: 51) 1cpu btclean
26 99b11c 80f630 4 ready 1cpu onmode_mon
32 a9a294 812b64 2 ready 1cpu sqlexec
113 b72a7c 810b78 2 ready 1cpu sqlexec
114 b86c8c 81244c 2 cond wait(netnorm) 1cpu sqlexec
115 b98a7c 812ef0 2 cond wait(netnorm) 1cpu sqlexec
116 bb4a24 80fd48 2 cond wait(netnorm) 1cpu sqlexec
117 bc6a24 81161c 2 cond wait(netnorm) 1cpu sqlexec
118 bd8a24 811290 2 ready 1cpu sqlexec
119 beae88 810f04 2 cond wait(await_MC1) 1cpu scan_1.0
120 a8ab48 8127d8 2 ready 1cpu scan_2.0
121 a96850 810460 2 ready 1cpu scan_2.1
122 ab6f30 8119a8 2 running 1cpu scan_2.2