Re: Bad performance when accessing a lot of small files

At 03:07 PM 12/19/2007, Alexandre Biancalana wrote:
On 12/19/07, Mike Tancsa <mike@xxxxxxxxxx> wrote:
> At 02:09 PM 12/19/2007, Alexandre Biancalana wrote:
>
> >The behavior that I'm observing and that want your help is when the
> >system is accessing some directory with many small files ( directories
> >with ~ 1 million of ~30kb files), the performance is very poor.
>
> Hi,

I'm using zfs, I think this change the things.. no ?

Hmmm, I dont know. Quite possibly / probably. Based on your values below, its not hitting the max if it were effected. I dont know anything about ZFS to know if there is some specific tuning that needs to be done for many files :(

---Mike

> Have you adjusted the dirhash value ? What does
>
> sysctl -a vfs.ufs | grep dirhash

# sysctl -a vfs.ufs | grep dirhash
vfs.ufs.dirhash_docheck: 0
vfs.ufs.dirhash_mem: 1410338
vfs.ufs.dirhash_maxmem: 2097152
vfs.ufs.dirhash_minsize: 2560


>
> show on your box ? Also, do you have a lot of UIDs in your passwd file ?

No.

# wc -l /etc/passwd
45 /etc/passwd
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