Re: [PATCH] proc/sysctl: prune stale dentries during unregistering

[Konstantin Khlebnikov]

On 10.02.2017 10:47, Al Viro wrote:
> On Fri, Feb 10, 2017 at 10:35:02AM +0300, Konstantin Khlebnikov wrote:
>
> > # time sysctl -a > /dev/null
> > real    1m12.806s
> > user    0m0.016s
> > sys     1m12.400s
> >
> > Currently only memory reclaimer could remove this garbage.
> > But without significant memory pressure this never happens.
> >
> > This patch collects sysctl inodes into list on sysctl table header and
> > prunes all their dentries once that table unregisters.
>
> I'd probably go for hlist, but that's mostly cosmetic difference; how about
> the matching stats *after* that patch?

dcache size doesn't grow endlessly, so stats are fine

# sysctl fs.dentry-state
fs.dentry-state = 92712	58376	45	0	0	0

# time sysctl -a &>/dev/null

real	0m0.013s
user	0m0.004s
sys	0m0.008s