Re: 13GB dcache+inode cache hash tables

[Daniel J Blueman <daniel@numascale-asia.com>]

On 25/06/2013 17:48, Eric Dumazet wrote:
> On Tue, 2013-06-25 at 16:56 +0800, Daniel J Blueman wrote:
>> As memory capacity increases, we see the dentry and inode cache hash
>> tables grow to wild sizes [1], eg 13GB is consumed on a 4.5TB system.
>>
>> Perhaps a better approach adds a linear component to an exponent to give
>> tuned scaling, given that spatial locality is an advantage in hash table
>> and careful use of resources.
>>
>> The same approach would fit to other hash tables (mount-cache, TCP
>> established, TCP bind, UDP, UDP-Lite, Dquot-cache) with different
>> coefficients, so perhaps we could generalise.
>>
>
> TCP hash table is limited to 512K slots, unless overridden.
> TCP bind limited to 64K slots.
> UDP limited to 64K slots.
>
>> If so what are reasonable reference points and assumptions?
>
> I do not know what you have in mind, please show us a patch ;)
[...]

Alright, I'll see what I can get together in the next week or so when I 
can fit it in.

Dan
-- 
Daniel J Blueman
Principal Software Engineer, Numascale Asia