Suspect regression. Using v 4.0.1 (Gentoo X86_64). Having just installed black (v22.1.0), reformatting produced multiple W503 messages. Attempted to utilize extended-ignore and reloaded/rescanned project. Warnings persisted. I ensured no W503/W504 ignores were present in code or configuration. Only after adding explicitly W503 to extended-ignore would flake8 be satisfied.

_Originally posted by

Rocksdb has a write option to set it low priority. Our pruners should use this option.

Other options that seems no brainer to enable:

1. use "multithreaded" flavor of the DB https://docs.rs/rocksdb/latest/rocksdb/type.DB.html#compatibility-and-multi-threaded-mode

2. these options upon DB open:

       let mut opts = Options::default();

        opts.increase_parallelism(num_cpus::