annotate mod_log_events_by_memory/README.markdown @ 5668:ecfd7aece33b

mod_measure_modules: Report module statuses via OpenMetrics Someone in the chat asked about a health check endpoint, which reminded me of mod_http_status, which provides access to module statuses with full details. After that, this idea came about, which seems natural. As noted in the README, it could be used to monitor that critical modules are in fact loaded correctly. As more modules use the status API, the more useful this module and mod_http_status becomes.
author Kim Alvefur <zash@zash.se>
date Fri, 06 Oct 2023 18:34:39 +0200
parents f781a90018f4
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1 This module compares the memory usage reported by Lua before and after
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2 each event and reports it to the log if it exceeds the configuration
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3 setting `log_memory_threshold` (in bytes).
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4
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5 ``` lua
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6 log_memory_threshold = 20*1024
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7 ```
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8
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9 If you are looking to identify memory leaks, please first read [Three
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10 kinds of memory
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11 leaks](https://blog.nelhage.com/post/three-kinds-of-leaks/).
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12
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13 Prosody runs on Lua which uses automatic memory management with garbage
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14 collection, so the numbers reported by this module are very likely to be
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15 useless for the purpose of identifying memory leaks. Large, but
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16 temporary, increases in memory usage can however highlight other kinds
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17 of performance problems and sometimes even provide hits for where to
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18 look for memory leaks.