Hi, On 2024-02-09 19:46:58 +0300, Nikita Malakhov wrote: > I agree with Heikki on most topics and especially the one he recommended > to publish your extension on GitHub, this tool is very promising for highly > loaded > systems, you will get a lot of feedback very soon. > > I'm curious about SpinLock - it is recommended for very short operations, > taking up to several instructions, and docs say that for longer ones it > will be > too expensive, and recommends using LWLock. Why have you chosen SpinLock? > Does it have some benefits here?
Indeed - e.g. end_tracing() looks to hold the spinlock for far too long for spinlocks to be appropriate. Use an lwlock. Random stuff I noticed while skimming: - pg_tracing.c should include postgres.h as the first thing - afaict none of the use of volatile is required, spinlocks have been barriers for a long time now - you acquire the spinlock for single increments of n_writers, perhaps that could become an atomic, to reduce contention? - I don't think it's a good idea to do memory allocations in the middle of a PG_CATCH. If the error was due to out-of-memory, you'll throw another error. Greetings, Andres Freund
