23 lines
923 B
Plaintext
23 lines
923 B
Plaintext
Demonstrations of gethostlatency, the Linux bpftrace/eBPF version.
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This traces host name lookup calls (getaddrinfo(), gethostbyname(), and
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gethostbyname2()), and shows the PID and command performing the lookup, the
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latency (duration) of the call in milliseconds, and the host string:
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# ./gethostlatency.bt
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Attaching 7 probes...
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Tracing getaddr/gethost calls... Hit Ctrl-C to end.
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TIME PID COMM LATms HOST
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02:52:05 19105 curl 81 www.netflix.com
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02:52:12 19111 curl 17 www.netflix.com
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02:52:19 19116 curl 9 www.facebook.com
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02:52:23 19118 curl 3 www.facebook.com
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In this example, the first call to lookup "www.netflix.com" took 81 ms, and
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the second took 17 ms (sounds like some caching).
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There is another version of this tool in bcc: https://github.com/iovisor/bcc
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The bcc version provides options to customize the output.
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