zulip

Author	SHA1	Message	Date
Alex Vandiver	800e38016a	queue_rate: Output to CSV, and run multiple prefetch values.	2021-11-16 11:48:50 -08:00
Anders Kaseorg	11741543da	python: Reformat with Black, except quotes. Signed-off-by: Anders Kaseorg <anders@zulip.com>	2021-02-12 13:11:19 -08:00
Anders Kaseorg	72d6ff3c3b	docs: Fix more capitalization issues. Signed-off-by: Anders Kaseorg <anders@zulip.com>	2020-10-23 11:46:55 -07:00
Alex Vandiver	d47637fa40	queue: Set a max consume timeout with SIGALRM. SIGALRM is the simplest way to set a specific maximum duration that queue workers can take to handle a specific message. This only works in non-threaded environments, however, as signal handlers are per-process, not per-thread. The MAX_CONSUME_SECONDS is set quite high, at 10s -- the longest average worker consume time is embed_links, which hovers near 1s. Since just knowing the recent mean does not give much information[1], it is difficult to know how much variance is expected. As such, we set the threshold to be such that only events which are significant outliers will be timed out. This can be tuned downwards as more statistics are gathered on the runtime of the workers. The exception to this is DeferredWorker, which deals with quite-long requests, and thus has no enforceable SLO. [1] https://www.autodesk.com/research/publications/same-stats-different-graphs	2020-10-06 17:26:14 -07:00
Alex Vandiver	8cf37a0d4b	queue: Add a tool to profile no-op enqueue and dequeue actions.	2020-10-06 17:26:14 -07:00