I wrote:
> I will run multiple tests and post the actual numbers.
I did run more extensive tests and did not bother writing down the numbers, and here's why: the unmodified Pg ran pgbench with a whopping average of 6.3% time in IO wait.
If I was able to totally eliminate that time (which is impossible), then the best we could hope for is a 7% increase in performance by skipping WAL of indexes.
On a related note, we currently have some indexes that are unsafe during recovery (GIST and Hash come to mind).
In the spirit of making Pg "safe at any speed," would it make sense to put some code in the recovery section that rebuilds all indexes whose integrity cannot be assured?
M
