Re: [nft PATCH] intervals: Do not sort cached set elements over and over again

[Phil Sutter <phil@nwl.cc>]

On Wed, Jun 15, 2022 at 09:36:11PM +0200, Pablo Neira Ayuso wrote:
> On Wed, Jun 15, 2022 at 07:33:29PM +0200, Phil Sutter wrote:
> > When adding element(s) to a non-empty set, code merged the two lists and
> > sorted the result. With many individual 'add element' commands this
> > causes substantial overhead. Make use of the fact that
> > existing_set->init is sorted already, sort only the list of new elements
> > and use list_splice_sorted() to merge the two sorted lists.
> > 
> > A test case adding ~25k elements in individual commands completes in
> > about 1/4th of the time with this patch applied.
> 
> Good.
> 
> Do you still like the idea of coalescing set element commands whenever
> possible?

Does it mess with error reporting? If not, I don't see a downside of
doing it.

With regards to the problem at hand, it seems like a feature to escape
the actual problem. Please keep in mind that my patch's improvement from
~4min down to ~1min is pretty lousy given that v1.0.1 completed the same
task in 0.3s.

IMHO the whole overlap detection/auto merging should happen as commit
preparation and not per command.

Cheers, Phil