Since mid December, tests started failing with ENOMEM while
submitting I/O requests.
Logs of failed tests show IO uring was used as backend, but we
never deliberately switched to IO uring. Investigation pointed
to it happening accidentaly in commit 1bac6b75dc,
which turned on IO uring for allowing native tool in production,
and picked linux-aio backend explicitly when initializing Scylla.
But it missed that seastar-based tests would pick the default
backend, which is io_uring once enabled.
There's a reason we never made io_uring the default, which is
that it's not stable enough, and turns out we made the right
choice back then and it apparently continue to be unstable
causing flakiness in the tests.
Let's undo that accidental change in tests by explicitly
picking the linux-aio backend for seastar-based tests.
This should hopefully bring back stability.
Refs #21968.
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Closesscylladb/scylladb#22695
(cherry picked from commit ce65164315)
Signed-off-by: Raphael S. Carvalho <raphaelsc@scylladb.com>
Closesscylladb/scylladb#22800
5f74b5fdff