[RFC] Bumping ufs.dirhash_maxmem to a larger value?

Chuck Swiger cswiger at mac.com
Sun Aug 7 18:57:47 GMT 2005


Xin LI wrote:
> It seems that vfs.ufs.dirhash_maxmem is set to 2MB.  I think this value
> is slightly too small for modern machines:
[ ... ]
> My proposal is to increase the default dirhash_maxmem value to at least
> 32MB or 64MB.  Any objections?

You are undoubtedly right that allocating only 2MB for dirhash on a modern 
machine which has, for example, 1GB of RAM is too small.

On the other hand, I've got several firewall boxes with only 128MB, and it's 
not reasonable to simply dedicate up to 64MB (half!) to dirhash without paying 
more attention to the amount of physical memory that is actually available.

How big should dirhash_maxmem be?  5-10% of available RAM, perhaps?

-- 
-Chuck



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