annotate mod_log_events_by_cpu_usage/README.markdown @ 4877:adc6241e5d16

mod_measure_process: Report the enforced limit The soft limit is what the kernel actually enforces, while the hard limit is is how far you can change the soft limit without privileges. Unless the process dynamically adjusts the soft limit, knowing the hard limit is not as useful as knowing the soft limit. Reporting the soft limit and the number of in-use FDs allows placing alerts on expressions like 'process_open_fds / process_max_fds >= 0.95'
author Kim Alvefur <zash@zash.se>
date Tue, 18 Jan 2022 18:55:20 +0100
parents c0bc97c0ba61
children
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c0bc97c0ba61 mod_log_events_by_cpu_usage: Log events where more than a certain amount of CPU time was spent
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1 This module logs events where more than a certain amount of CPU time was
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2 spent.
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3
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4 ``` lua
c0bc97c0ba61 mod_log_events_by_cpu_usage: Log events where more than a certain amount of CPU time was spent
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5 log_cpu_threshold = 0.01 -- in seconds, so this is 10 milliseconds
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6 ```
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7
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8 Uses the Lua
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9 [`os.clock()`](http://www.lua.org/manual/5.2/manual.html#pdf-os.clock)
c0bc97c0ba61 mod_log_events_by_cpu_usage: Log events where more than a certain amount of CPU time was spent
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10 function to estimate CPU usage.