> Hi, > > I have very bad bgwriter statistics on a server which runs since many > weeks > and it is still the same after a recent restart. > There are roughly 50% of buffers written by the backend processes and the > rest by checkpoints. > The statistics below are from a server with 140GB RAM, 32GB shared_buffers > and a runtime of one hour. > > As you can see in the pg_buffercache view that there are most buffers > without usagecount - so they are as free or even virgen as they can be. > At the same time I have 53% percent of the dirty buffers written by the > backend process.
There are some nice old threads dealing with this - see for example