Re: [PATCH libnetfilter_queue 0/1] New pktb_usebuf() function

[Duncan Roe <duncan_roe@optusnet.com.au>]

Hi Pablo,

On Tue, Dec 10, 2019 at 10:26:33PM +1100, Duncan Roe wrote:
> pktb_usebuf() is a copy of pktb_alloc() with the first part modified to use
> a supplied buffer rather than calloc() one. I thought this would give a
> measurable performance boost and it does.
> All the code after the memset() call is common to pktb_alloc(). If you like,
> I can submit a v2 with this code in a static function called by both.
>
> Duncan Roe (1):
>   src: Add alternative function to pktb_alloc to avoid malloc / free
>     overhead
>
>  include/libnetfilter_queue/pktbuff.h |  2 +
>  src/extra/pktbuff.c                  | 82 ++++++++++++++++++++++++++++++++++++
>  2 files changed, 84 insertions(+)
>
> --
> 2.14.5
>
After a day or so of testing, it appears pktb_usebuf() saves 6% overall CPU over
pktb_alloc() in a program similar to libnetfilter_queue/examples/nf-queue.c (but
not printing every packet). The variance is quite high, so plus or minus 1%. Can
supply more details of testing methodology if you want them.

Overall I would say 6% is a worthwhile saving.

What about it?

Cheers ... Duncan.