Re: seq scan cache vs. index cache smackdown

In the last exciting episode, merlin.moncure@rcsonline.com ("Merlin Moncure") wrote:
>> It seems inevitable that Postgres will eventually eliminate that
>> redundant layer of buffering. Since mmap is not workable, that
>> means using O_DIRECT to read table and index data.
>
> What about going the other way and simply letting the o/s do all the
> caching?  How bad (or good) would the performance really be?

I'm going to see about taking this story to OLS (Ottawa Linux
Symposium) in July and will see what hearing I can get.  There are
historically some commonalities in the way this situation is regarded,
in that there was _long_ opposition to the notion of having unbuffered
disk devices.

If there's more "story" that definitely needs to be taken, let me
know...
--
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