Re: how to calculate or know seq_scan scan how many blocks every time

On 07/25/2012 07:38 PM, leo xu wrote:
> hello:
>     i know oracle scatter read blocks,can set db_file_multiblock_read_count
> every time,
>     i see postgres,it exists scatter read blocks,it is seq_scan,how to know
> scan many bloks every time?
>

If I understand correctly, you want to have a sequential scan read from
more than one place at once.

This is not currently supported.

The effective_io_concurrency setting would be where you would set it,
but it does not affect sequential scans at the moment.

--
Craig Ringer