Re: hash table sizes

[Anton Blanchard]

> That was a concern to me too. However, on IA64, all page structs are
> in the vmalloc region (it isnt allocated by vmalloc but is in the same
> region as vmalloc'ed pages. They are mapped with 16k pages instead of
> the 64MB pages used for memory allocated by kmalloc).
> 
> Before switching to 16K pages for the page structs, we made numerous
> performance measurements. As far as we could tell, there was no
> performce degradation caused by the smaller pages. It seems to me that
> if page structs are ok being mapped by 16k pages, the hash tables
> would be ok too. 

OK, on ppc64 with a 4kB base pagesize Id be more worried about using the
vmalloc region.

Anton
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