c29d517558
unmodified. For others we'll need to add the missing probes and adjust. This is not attached to the build.
63 lines
2.5 KiB
Plaintext
63 lines
2.5 KiB
Plaintext
This is a demonstration of the dispqlen.d script,
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Here we run it on a single CPU desktop,
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# dispqlen.d
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Sampling... Hit Ctrl-C to end.
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^C
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CPU 0
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value ------------- Distribution ------------- count
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< 0 | 0
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0 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ 1790
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1 |@@@ 160
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2 | 10
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3 | 0
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The output shows the length of the dispatcher queue is mostly 0. This is
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evidence that the CPU is not very saturated. It does not indicate that the
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CPU is idle - as we are measuring the length of the queue, not what is
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on the CPU.
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Here it is run on a multi CPU server,
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# dispqlen.d
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Sampling... Hit Ctrl-C to end.
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^C
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CPU 1
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value ------------- Distribution ------------- count
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< 0 | 0
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0 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ 1573
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1 |@@@@@@@@@ 436
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2 | 4
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3 | 0
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CPU 4
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value ------------- Distribution ------------- count
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< 0 | 0
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0 |@@@@@@@@@@@@@@@@@@@@@@ 1100
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1 |@@@@@@@@@@@@@@@@@@ 912
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2 | 1
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3 | 0
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CPU 0
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value ------------- Distribution ------------- count
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< 0 | 0
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0 |@@@@@@@@@@@@@@@@@ 846
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1 |@@@@@@@@@@@@@@@@@@@@@@@ 1167
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2 | 0
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CPU 5
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value ------------- Distribution ------------- count
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< 0 | 0
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0 |@@@@@@@@ 397
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1 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ 1537
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2 |@@ 79
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3 | 0
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The above output shows that threads are queueing up on CPU 5 much more than
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CPU 0.
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