ZFS directory with a large number of files

[Daniel O'Connor]

On 06/08/2011, at 5:17, Patrick M. Hausen wrote:
> Am 05.08.2011 um 17:12 schrieb Christian Weisgerber:
>> Daniel Kalchev <daniel at digsys.bg> wrote:
>> 
>>> On 02.08.11 12:46, Daniel O'Connor wrote:
>>>> I am pretty sure UFS does not have this problem. i.e. once you 
>>>> delete/move the files out of the directory its performance would be 
>>>> good again. 
>>> 
>>> UFS would be the classic example of poor performance if you do this.
>> 
>> "Classic" indeed.  UFS dirhash has pretty much taken care of this
>> a decade ago.
> 
> While dirhash is quite an improvement, it is definitely no silver bullet.
> 
> When I asked Kirk McKusick at last year's EuroBSDCon if having
> a six-figure number of files in a single directory was a clever idea
> (I just had a customer who ran into that situation), he just smiled
> and shook his head.

Ahh, but OP had moved these files away and performance was still poor.. _that_ is the bug.

--
Daniel O'Connor software and network engineer
for Genesis Software - http://www.gsoft.com.au
"The nice thing about standards is that there
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