Re: AW: [HACKERS] mmap and MAP_ANON

>
> >> - Could we use mmap:ing of files at a higher level then
> >>   src/backend/strorage/ipc/ipc.c to get even better performance
> >>   and cleaness?
> >
> >Yes, we could use mmap() to map the actual files.  I will post time
> >timings on this soon.
>
> I do not think this will be a practicable solution, since it would mean the whole db
> has to mmap'ed. This means there has to be enough virtual memory to hold
> the complete database, or at least one table at a time. Or do I understand this wrong ??

We can map parts of the table, even in 8k chunks.  However, looking at
my sequential scan timing tests, it would be slower.

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