annotate mod_log_events_by_memory/README.markdown @ 5173:460f78654864

mod_muc_rtbl: also filter messages This was a bit tricky because we don't want to run the JIDs through SHA256 on each message. Took a while to come up with this simple plan of just caching the SHA256 of the JIDs on the occupants. This will leave some dirt in the occupants after unloading the module, but that should be ok; once they cycle the room, the hashes will be gone. This is direly needed, otherwise, there is a tight race between the moderation activities and the actors joining the room.
author Jonas Schäfer <jonas@wielicki.name>
date Tue, 21 Feb 2023 21:37:27 +0100
parents f781a90018f4
children
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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.