Hi, On 2023-07-31 21:03:07 +0900, Masahiko Sawada wrote: > Regarding the patch, I have a comment: > > -- Test that reuse of strategy buffers and reads of blocks into these reused > --- buffers while VACUUMing are tracked in pg_stat_io. > +-- buffers while VACUUMing are tracked in pg_stat_io. If there is sufficient > +-- demand for shared buffers from concurrent queries, some blocks may be > +-- evicted from the strategy ring before they can be reused. In such cases > +-- this, the backend will evict a block from a shared buffer outside of the > +-- ring and add it to the ring. This is considered an eviction and not a > reuse. > > The new comment seems not to be accurate if my understanding is correct. How > about the following? > > Test that reuse of strategy buffers and reads of blocks into these > reused buffers while VACUUMing are tracked in pg_stat_io. If there is > sufficient demand for shared buffers from concurrent queries, some > buffers may be pinned by other backends before they can be reused. In > such cases, the backend will evict a buffer from a shared buffer > outside of the ring and add it to the ring. This is considered an > eviction and not a reuse.
I integrated the suggested change of the comment and tweaked it a bit more. And finally pushed the fix. Sorry that it took so long. Greetings, Andres Freund
