Hi, On 2025-03-25 12:39:56 -0700, Noah Misch wrote: > On Tue, Mar 25, 2025 at 02:58:37PM -0400, Andres Freund wrote: > > I don't know if that's an intentional or unintentional behavioral > > difference. > > > > There are 2 1/2 ways around this: > > > > 1) Stop using IOSQE_ASYNC heuristic > > 2a) Wait for all in-flight IOs when any FD gets closed > > 2b) Wait for all in-flight IOs using FD when it gets closed > > > > Given that we have clear evidence that io_uring doesn't completely support > > closing FDs while IOs are in flight, be it a bug or intentional, it seems > > clearly better to go for 2a or 2b. > > Agreed. If a workload spends significant time on fd.c closing files, I > suspect that workload already won't have impressive benchmark numbers. > Performance-seeking workloads will already want to tune FD usage high enough > to keep FDs long-lived. So (1) clearly loses, and neither (2a) nor (2b) > clearly beats the other. I'd try (2b) first but, if complicated, quickly > abandon it in favor of (2a). What other considerations could be important?
The only other consideration I can think of is whether this should happen for all io_methods or not. I'm inclined to do it via a bool in IoMethodOps, but I guess one could argue it's a bit weird to have a bool in a struct called *Ops. Greetings, Andres Freund
