Re: [RFC PATCH 0/7] evacuate struct page from the block layer

[Wols Lists]

On 20/03/15 20:31, Matthew Wilcox wrote:
> Ah!  I've looked at that a couple of times as well.  I asked our database
> performance team what impact freeing up the memmap would have on their
> performance.  They told me that doubling the amount of memory generally
> resulted in approximately a 40% performance improvement.  So freeing up
> 1.5% additional memory would result in about 0.6% performance improvement,
> which I thought was probably too small a return on investment to justify
> turning memmap into a two-level data structure.

Don't get me started on databases! This is very much a relational
problem, other databases don't suffer like this.

(imho relational theory is totally inappropriate for an engineering
problem, like designing a database engine ...)

Cheers,
Wol
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