On Tue, 7 Jan 2025 at 15:46, James Carter <jwcart2@xxxxxxxxx> wrote:
>
> On Mon, Dec 30, 2024 at 8:51 AM Christian Göttsche
> <cgoettsche@xxxxxxxxxxxxx> wrote:
> >
> > From: Christian Göttsche <cgzones@xxxxxxxxxxxxxx>
> >
> > Bump the maximum specification node depth from 3 to 4 based on updated
> > benchmark on Fedora 41:
> >
>
> I am not sure I understand these numbers.
>
> > Benchmark 1: /tmp/destdir3/sbin/restorecon -vRn /
> > Time (mean ± σ): 1.397 s ± 0.018 s [User: 0.755 s, System: 0.641 s]
> > Range (min … max): 1.353 s … 1.419 s 20 runs
> >
> Is this for depth 3?
Yes, I should have made this more clear.
> > Benchmark 1: /tmp/destdir4/sbin/restorecon -vRn /
> > Time (mean ± σ): 1.376 s ± 0.021 s [User: 0.737 s, System: 0.637 s]
> > Range (min … max): 1.348 s … 1.414 s 20 runs
> >
> Depth 4?
>
> > Benchmark 1: /tmp/destdir5/sbin/restorecon -vRn /
> > Time (mean ± σ): 1.389 s ± 0.021 s [User: 0.748 s, System: 0.640 s]
> > Range (min … max): 1.351 s … 1.420 s 20 runs
> Depth 5?
>
> I see the comment below talks about more memory, how much more memory
> is required for a depth of 4?
The maximum memory usage for `selabel_lookup -b file -k /usr/bin/bash`
for all three depths is in the range 3800-4000kB, with depth 5
occasionally being at 4060kB.
>
> Thanks,
> Jim
>
> > ---
> > libselinux/src/label_file.h | 6 +++---
> > 1 file changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/libselinux/src/label_file.h b/libselinux/src/label_file.h
> > index 597b756e..41b2a939 100644
> > --- a/libselinux/src/label_file.h
> > +++ b/libselinux/src/label_file.h
> > @@ -105,10 +105,10 @@ struct literal_spec {
> > * Max depth of specification nodes
> > *
> > * Measure before changing:
> > - * - 2 leads to slower lookup
> > - * - >4 require more memory (and allocations) for no performance gain
> > + * < leads to slower lookup
> > + * > require more memory (and allocations) for no performance gain
> > */
> > -#define SPEC_NODE_MAX_DEPTH 3
> > +#define SPEC_NODE_MAX_DEPTH 4
> >
> > /* A specification node */
> > struct spec_node {
> > --
> > 2.45.2
> >
> >
