prometheus

The Prometheus monitoring system and time series database.

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Tree: ab97c9e09f

TJ Hoplock ab97c9e09f fix!: stop unbounded memory usage from query log Resolves: #15433 When I converted prometheus to use slog in #14906, I update both the `QueryLogger` interface, as well as how the log calls to the `QueryLogger` were built up in `promql.Engine.exec()`. The backing logger for the `QueryLogger` in the engine is a `util/logging.JSONFileLogger`, and it's implementation of the `With()` method updates the logger the logger in place with the new keyvals added onto the underlying `slog.Logger`, which means they get inherited onto everything after. All subsequent calls to `With()`, even in later queries, would continue to then append on more and more keyvals for the various params and fields built up in the logger. In turn, this causes unbounded growth of the logger, leading to increased memory usage, and in at least one report was the likely cause of an OOM kill. More information can be found in the issue and the linked slack thread. This commit does a few things: - It was referenced in feedback in #14906 that it would've been better to not change the `QueryLogger` interface if possible, this PR proposes changes that bring it closer to alignment with the pre-3.0 `QueryLogger` interface contract - reverts `promql.Engine.exec()`'s usage of the query logger to the pattern of building up an array of args to pass at once to the end log call. Avoiding the repetitious calls to `.With()` are what resolve the issue with the logger growth/memory usage. - updates the scrape failure logger to use the update `QueryLogger` methods in the contract. - updates tests accordingly - cleans up unused methods Builds and passes tests successfully. Tested locally and confirmed I could no longer reproduce the issue/it resolved the issue. Signed-off-by: TJ Hoplock <t.hoplock@gmail.com>		2 days ago
..
dedupe.go	chore(deduper): add compile check that slog.Handler int is satisfied	7 days ago
dedupe_test.go	chore!: adopt log/slog, remove go-kit/log	2 months ago
file.go	fix!: stop unbounded memory usage from query log	2 days ago
file_test.go	fix!: stop unbounded memory usage from query log	2 days ago