Re: Index Scans become Seq Scans after VACUUM ANALYSE

Bruce Momjian wrote:
> Now, with larger RAM and disk sizes, it may be time to consider larger
> page sizes, like 32k pages. That reduces the granularity of the cache,
> but it may have other performance advantages that would be worth it.
>
> What people are actually suggesting with the read-ahead for sequential
> scans is basically a larger block size for sequential scans than for
> index scans. While this makes sense, it may be better to just increase
> the block size overall.

I have seen performance improvements by using 16K blocks over 8K blocks in
sequential scans of large tables.

I am investigating the performance difference between 16K and 8K block sizes on
one of my systems. I'll let you know what I see. I am using pgbench for generic
performance levels.

If you would like to see any extra data, just let me know.