fragments processing

[Max]

Hello, Kristof.


20.05.2016 11:53, Kristof Provost пишет:
> Hi Max,
>
>
> On 19 May 2016, at 19:49, Max wrote:
>> The number of used frags (almost) never decreases. I don't have 
>> enough experience in programming. But I guess that the problem may be 
>> in "frag->fr_timeout = time_second;" in pf_fillup_fragment() 
>> (pf_norm.c). It should be "frag->fr_timeout = time_uptime;". 
>> Actually, I don't now the difference between those variables. So, 
>> correct me if I'm wrong.
>>
> I think you’re right. If I’m reading the code right time_second is 
> unix time,
> but time_uptime is the number of seconds the system has been up.
>
> Either one should work, but we have to be consistent.
> The rest of the code seems to use time_uptime, so this untested patch 
> should fix your problem.
>
> diff --git a/sys/netpfil/pf/pf_norm.c b/sys/netpfil/pf/pf_norm.c
> index a2841a2..dbc8818 100644
> --- a/sys/netpfil/pf/pf_norm.c
> +++ b/sys/netpfil/pf/pf_norm.c
> @@ -374,7 +374,7 @@ pf_fillup_fragment(struct pf_fragment_cmp *key, 
> struct pf_frent *frent,
>                 }
>
>                 *(struct pf_fragment_cmp *)frag = *key;
> -               frag->fr_timeout = time_second;
> +               frag->fr_timeout = time_uptime;
>                 frag->fr_maxlen = frent->fe_len;
>                 TAILQ_INIT(&frag->fr_queue);
>

I rebuilt the kernel. It seems the problem is gone.


>> P.P.S. I confirm the bug 
>> https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=201519.
>
> It’s on my list, but unfortunately it’s a very long list.

I'll wait for the patch. Thank you.

>
> Regards,
> Kristof

Here are some statistics:


# sh -c "while true ; do date; { vmstat -z; pfctl -si; } | sed -n 
'1p;/frag/p'; echo; sleep 5; done"
Fri May 20 13:07:11 MSK 2016
ITEM                   SIZE  LIMIT     USED     FREE      REQ FAIL SLEEP
pf frags:               120,      0,       0,     132,      71, 0,   0
pf frag entries:         40,   5000,       0,     600,     147, 0,   0
   fragment                               4            0.0/s

...

Fri May 20 16:07:16 MSK 2016
ITEM                   SIZE  LIMIT     USED     FREE      REQ FAIL SLEEP
pf frags:               120,      0,       0,     132,     761, 0,   0
pf frag entries:         40,   5000,       0,     600,    1531, 0,   0
   fragment                               4            0.0/s

Fri May 20 16:07:21 MSK 2016
ITEM                   SIZE  LIMIT     USED     FREE      REQ FAIL SLEEP
pf frags:               120,      0,       1,     131,     771, 0,   0
pf frag entries:         40,   5000,       1,     599,    1551, 0,   0
   fragment                               5            0.0/s

...

Fri May 20 16:07:56 MSK 2016
ITEM                   SIZE  LIMIT     USED     FREE      REQ FAIL SLEEP
pf frags:               120,      0,       1,     131,     771, 0,   0
pf frag entries:         40,   5000,       1,     599,    1551, 0,   0
   fragment                               5            0.0/s

Fri May 20 16:08:01 MSK 2016
ITEM                   SIZE  LIMIT     USED     FREE      REQ FAIL SLEEP
pf frags:               120,      0,       0,     132,     771, 0,   0
pf frag entries:         40,   5000,       0,     600,    1551, 0,   0
   fragment                               5            0.0/s

...

Fri May 20 16:11:12 MSK 2016
ITEM                   SIZE  LIMIT     USED     FREE      REQ FAIL SLEEP
pf frags:               120,      0,       0,     132,     771, 0,   0
pf frag entries:         40,   5000,       0,     600,    1551, 0,   0
   fragment                               5            0.0/s

Fri May 20 16:11:17 MSK 2016
ITEM                   SIZE  LIMIT     USED     FREE      REQ FAIL SLEEP
pf frags:               120,      0,       1,     131,     781, 0,   0
pf frag entries:         40,   5000,       1,     599,    1571, 0,   0
   fragment                               6            0.0/s

...

Fri May 20 16:11:42 MSK 2016
ITEM                   SIZE  LIMIT     USED     FREE      REQ FAIL SLEEP
pf frags:               120,      0,       1,     131,     781, 0,   0
pf frag entries:         40,   5000,       1,     599,    1571, 0,   0
   fragment                               6            0.0/s

Fri May 20 16:11:47 MSK 2016
ITEM                   SIZE  LIMIT     USED     FREE      REQ FAIL SLEEP
pf frags:               120,      0,       0,     132,     781, 0,   0
pf frag entries:         40,   5000,       0,     600,    1571, 0,   0
   fragment                               6            0.0/s