Sorry, 'someone' launches some kind of batches without telling.
Marc MILLAS Senior Architect +33607850334 www.mokadb.com On Fri, Apr 25, 2025 at 3:42 PM Marc Millas <marc.mil...@mokadb.com> wrote: > hello, > > got something strange to me: > Same db ie. same data, around 1.2TB,one on pg13, one on pg16 > same 16 GB of shared_buffers, > I am the single user. > both have track_io_timing on > > on pg13, if I run a big request with explain (analyze,buffers), > I see around 6 GB read > if I do rerun the very same request, no more read(s), all data in the > shared buffers cache. fine > If I check with pg_buffercache what's in it, I see the biggest tables of > my request within the biggest users (in number of blocks used). All this is > fine. > > next, if I do the very same on the pg16 machine, whatever the number of > times I rerun the explain (analyze, buffers) of the same request, each > time, the explain shows the same volume of reads. again and again. > If I check with pg_buffercache, the set of objects stay the same, WITHOUT > the objects of my request, just like if those objects where sticky. > > any idea ? > > thanks > > Marc MILLAS > Senior Architect > +33607850334 > www.mokadb.com > >
