[Pdns-users] stuck tcp sessions on recursor

[Charles Sprickman]

On Thu, 24 Feb 2011, bert hubert wrote:

> On Thu, Feb 24, 2011 at 03:06:12PM -0500, Charles Sprickman wrote:
>>> this definitely sounds like 3.3 material!
>>
>> So far so good, nearly 500,000 tcp queries without any lingering sockets.
>
> Good!
>
>> Totally unrelated, but I see a stat that's not mentioned in the
>> docs: "no-packet-error 492682".  What is that, and is it any cause
>> for concern?
>
> It is a debugging metric we added to see if our event multiplexing
> infrastructure is operating as well as it could. Can you give me the output
> of 'rec_control get-all' after some time of operation?

OK, so this has been running since thursday afternoon, so there should be 
a good amount of data:

all-outqueries  6399778
dlg-only-drops  0
dont-outqueries 7398
outgoing-timeouts       135883
tcp-outqueries  18829
throttled-out   55224
throttled-outqueries    55224
unreachables    16954
answers-slow    102824
answers0-1      4719448
answers1-10     293890
answers10-100   2222358
answers100-1000 838796
case-mismatches 0
chain-resends   303582
client-parse-errors     0
edns-ping-matches       0
edns-ping-mismatches    0
ipv6-outqueries 0
no-packet-error 73902632
noedns-outqueries       6418288
noerror-answers 564585493
noping-outqueries       0
nsset-invalidations     3928
nxdomain-answers        1993006
over-capacity-drops     0
qa-latency      0
questions       567237874
resource-limits 0
server-parse-errors     87
servfail-answers        38604
spoof-prevents  0
tcp-client-overflow     0
tcp-questions   1067417
unauthorized-tcp        0
unauthorized-udp        0
unexpected-packets      7
cache-entries   1000032
cache-hits      4714245
cache-misses    3463107
concurrent-queries      5
negcache-entries        81352
nsspeeds-entries        3792
packetcache-entries     500035
packetcache-hits        559223271
packetcache-misses      7109939
sys-msec        30349461
tcp-clients     0
throttle-entries        80
uptime  309672
user-msec       24840697

> It is probably of no concern, but it might waste some CPU cycles. Probably
> no-packet-error is a lot smaller than your number of questions and
> outqueries.

Yep, total questions is 567237874, no-packet-error is 73902632, so roughly 
maybe 1/6 of all questions.

Let me know if you want to see any other data...

Thanks,

Charles

>> I'm really happy with the recursor so far, we previously used
>> dnscache and we're seeing about 1/5 the cpu usage and I believe
>> we're also answering queries that we weren't before - our overall
>> qps went up quite a bit after the switch.
>
> great!
>
> 	Bert
>