63 lines
2.5 KiB
Plaintext
63 lines
2.5 KiB
Plaintext
|
This is a demonstration of the dispqlen.d script,
|
||
|
|
||
|
|
||
|
Here we run it on a single CPU desktop,
|
||
|
|
||
|
# dispqlen.d
|
||
|
Sampling... Hit Ctrl-C to end.
|
||
|
^C
|
||
|
CPU 0
|
||
|
value ------------- Distribution ------------- count
|
||
|
< 0 | 0
|
||
|
0 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ 1790
|
||
|
1 |@@@ 160
|
||
|
2 | 10
|
||
|
3 | 0
|
||
|
|
||
|
The output shows the length of the dispatcher queue is mostly 0. This is
|
||
|
evidence that the CPU is not very saturated. It does not indicate that the
|
||
|
CPU is idle - as we are measuring the length of the queue, not what is
|
||
|
on the CPU.
|
||
|
|
||
|
|
||
|
|
||
|
Here it is run on a multi CPU server,
|
||
|
|
||
|
# dispqlen.d
|
||
|
Sampling... Hit Ctrl-C to end.
|
||
|
^C
|
||
|
CPU 1
|
||
|
value ------------- Distribution ------------- count
|
||
|
< 0 | 0
|
||
|
0 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ 1573
|
||
|
1 |@@@@@@@@@ 436
|
||
|
2 | 4
|
||
|
3 | 0
|
||
|
|
||
|
CPU 4
|
||
|
value ------------- Distribution ------------- count
|
||
|
< 0 | 0
|
||
|
0 |@@@@@@@@@@@@@@@@@@@@@@ 1100
|
||
|
1 |@@@@@@@@@@@@@@@@@@ 912
|
||
|
2 | 1
|
||
|
3 | 0
|
||
|
|
||
|
CPU 0
|
||
|
value ------------- Distribution ------------- count
|
||
|
< 0 | 0
|
||
|
0 |@@@@@@@@@@@@@@@@@ 846
|
||
|
1 |@@@@@@@@@@@@@@@@@@@@@@@ 1167
|
||
|
2 | 0
|
||
|
|
||
|
CPU 5
|
||
|
value ------------- Distribution ------------- count
|
||
|
< 0 | 0
|
||
|
0 |@@@@@@@@ 397
|
||
|
1 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ 1537
|
||
|
2 |@@ 79
|
||
|
3 | 0
|
||
|
|
||
|
The above output shows that threads are queueing up on CPU 5 much more than
|
||
|
CPU 0.
|
||
|
|