On Fri, Sep 16, 2016 at 9:09 AM, Pavan Deolasee <pavan.deola...@gmail.com> wrote:
> > I also realised that we can compact the TID array in step (b) above > because we only need to store 17 bits for block numbers (we already know > which 1GB segment they belong to). Given that usable offsets are also just > 13 bits, TID array needs only 4 bytes per TID instead of 6. > > Actually this seems like a clear savings of at least 30% for all use cases, at the cost of allocating in smaller chunks and doing some transformations. But given the problem we are trying to solve, seems like a small price to pay. Thanks, Pavan -- Pavan Deolasee http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services
