Alvaro Herrera <alvherre@alvh.no-ip.org> writes:
> In light of this, may I ask whether it makes sense to compare the
> performance of two runs with similar shared_buffer settings? With
> O_DIRECT, I understand from this manpage that the OS is going to do
> little or no page caching, so shared_buffers should be increased to
> account for this fact.
> Am I missing something?
O_DIRECT is only being used for WAL page writes (or I sure hope so
anyway), so shared_buffers should be irrelevant.
regards, tom lane