At the end is the patch I mentioned against pftop.c v1.37, using a guard digit.
WARNING: Untested. I couldn't even try to compile it.
At this point I don't see anything wrong with your patch, Mike.
--------------------------------------------
On Mon, 5/15/17, Mike Belopuhov <m...@belopuhov.com> wrote:
Subject: Re: pf queue definition: bandwidth resolution problem
To: "Carl Mascott" <cmasc...@yahoo.com>
Cc: "Theo Buehler" <t...@math.ethz.ch>, tech@openbsd.org
Date: Monday, May 15, 2017, 3:28 PM
On Sun, May 14, 2017 at 21:08 +0000, Carl
Mascott wrote:
> OK, I was indeed missing
something. Thanks, Theo and Mike.
>
> I think I see another very minor problem,
though.
> Let the pf BW be 9,999,999.
> Shift right 3 digits (divide by 1000) :
yields 9,999K.
> (If we were doing
floating point arithmetic, would yield 9,999.999K.)
> You (Mike) don't round this,
presumably to avoid overflow to 10,000 (5 digits).
> However, since (i < 3) it could have
been rounded and scaled again, to 10M.
>
Slightly more accurate but not a big deal.
>
You're right, initially I had a "<=
9999" there but then I got
sidetracked
with a hypothetical problem that right now seems
like my imagination. I've double checked
numbers and indeed,
it should be "if
(rtmp <= 9999)".
>
>
--------------------------------------------
> On Sun, 5/14/17, Theo Buehler <t...@math.ethz.ch>
wrote:
>
> Subject:
Re: pf queue definition: bandwidth resolution problem
> To: tech@openbsd.org
> Date: Sunday, May 14, 2017, 4:35 PM
>
> On Sun, May 14,
2017 at 08:29:18PM +0000, Carl
>
Mascott wrote:
> > It looks to me
like you
> are rounding on each
iteration of the for-loop:
> >
> > + for (i = 0;
> rate > 9999 && i <= 3;
i++) {
> > + rtmp = rate
/ 1000;
> > + if (rtmp
< 9999)
>
>
This is only true in the last
>
iteration.
>
>
> + rtmp
> += (rate
% 1000) / 500;
> > +
> rate = rtmp;
> >
+ }
> >
>
> Am I missing
> something?
>
>
>
--- pftop.c.old 2017-05-14 09:51:58.620737200 -0400
+++ pftop.c 2017-05-16 14:01:08.184811800 -0400
@@ -1608,7 +1608,7 @@
void
print_queue_node(struct pfctl_queue_node *node)
{
- u_int rate;
+ u_int64_t rate;
int i;
double interval, pps, bps;
static const char unit[] = " KMG";
@@ -1624,9 +1624,22 @@
// XXX: missing min, max, burst
tb_start();
rate = node->qs.linkshare.m2.absolute;
- for (i = 0; rate >= 1000 && i <= 3; i++)
- rate /= 1000;
- tbprintf("%u%c", rate, unit[i]);
+ rate *= 10UL;
+ for (i = 0; rate > 99999UL && i <= 3; i++)
+ rate /= 1000UL;
+ if (rate % 10UL >= 5UL) {
+ rate += 10UL; /* LSD incorrect, don't care */
+ if (rate > 99999UL) {
+ if (i < 3) {
+ rate /= 1000UL;
+ i++;
+ }
+ else
+ rate -= 10UL;
+ }
+ }
+ rate /= 10UL;
+ tbprintf("%u%c", (unsigned) rate, unit[i]);
print_fld_tb(FLD_BANDW);
if (node->qstats.valid && node->qstats_last.valid)
