question: does pyvips lock the GIL?

[machineonamission]

If i were to call libvips functions inside an async loop using a ThreadPoolExecutor, would it block the main loop? or should I use a ProcessPoolExecutor

[jcupitt]

pyvips doesn't lock the GIL itself, but I think cffi (pyvips uses this to call into the libvips binary) will lock around each call. You should check, of course.

Most libvips calls are quick, but it will block during things like write_to_file, or max.