On Tue, Mar 25, 2025 at 04:07:35PM -0400, Andres Freund wrote: > On 2025-03-25 12:39:56 -0700, Noah Misch wrote: > > On Tue, Mar 25, 2025 at 02:58:37PM -0400, Andres Freund wrote: > > > 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.
Either way is fine, I think. > 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. That wouldn't bother me. IndexAmRoutine has many bools, and "Ops" is basically a synonym of "Routine".
