ZFS directory with a large number of files

Daniel O'Connor doconnor at gsoft.com.au
Tue Aug 2 09:58:40 UTC 2011

On 02/08/2011, at 18:38, Jeremy Chadwick wrote:
> On Tue, Aug 02, 2011 at 08:39:03AM +0100, seanrees at gmail.com wrote:
>> On my FreeBSD 8.2-S machine (built circa 12th June), I created a
>> directory and populated it over the course of 3 weeks with about 2
>> million individual files.
> I'll keep this real simple:
> Why did you do this?
> I hope this was a stress test of some kind.  If not:
> This is the 2nd or 3rd mail in recent months from people saying "I
> decided to do something utterly stupid with my filesystem[1] and now I'm
> asking why performance sucks".
> Why can people not create proper directory tree layouts to avoid this
> problem regardless of what filesystem is used?  I just don't get it.
> [1]: Applies to any filesystem, not just ZFS.  There was a UFS one a
> month or two ago too…

The problem is that he is being punished with shitty FS performance even though the directory structure is now non-silly.

It sounds like the FS hasn't GC'd some (now unneeded) metadata..

Daniel O'Connor software and network engineer
for Genesis Software - http://www.gsoft.com.au
"The nice thing about standards is that there
are so many of them to choose from."
  -- Andrew Tanenbaum
GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C

More information about the freebsd-stable mailing list