On Sat, Sep 27, 2008 at 4:33 PM, John Huttley <John@xxxxxxxxxxxxxxxxxx> wrote: > > > > this is part of the trade-offs of MVCC. > > > was... was a part of the trade-offs. > > You are thinking of HOT? > I don't think it applies in the case of full table updates?? Sure, you just need a table with plenty of empty space in it, either from vacuumed previous deletes / inserts or with a low fill factor like 50%. > It's really an effect of parallel updates / writes / accesses, and is > always an issue for a database running on a poor storage subsystem. A > db with a two drive mirror set is always going to be at a disadvantage > to one running on a dozen or so drives in a RAID-10 > > Oh well, I'm forever going to be disadvantaged. Why? A decent caching raid controller and a set of 4 to 8 SATA drives can make a world of difference and the cost is not that high for the gain in performance. Even going to 4 drives in a software RAID-10 can make a lot of difference in these situations, and that can be done with spare machines and hard drives.
