[nsd-users] NSD TCP performance
nsd at dclg.ca
nsd at dclg.ca
Fri Nov 9 17:06:20 UTC 2007
>>>>> "W" == W C A Wijngaards <W.C.A.> writes:
W> -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1
W> Colm MacCarthaigh wrote:
>> On Thu, Nov 08, 2007 at 06:30:56PM -0800, Aaron Hopkins wrote:
>>> On Thu, 8 Nov 2007, nsd at dclg.ca wrote:
>>>> NSD always sends the two byte response size as a separate TCP
>>>> packet (causing the requestor to send a separate ACK) to the main
>>>> body of the request.
>>> I reported this in May 2006. Found in nsd-3.0.6/doc/TODO:
>>> - From Aaron Hopkins: write tcp length and tcp data in one write
>>> operation, instead of multiple calls to write. Avoids Nagle algo
>>> delay in this case. preallocate 2 bytes in front of buffer to put
>>> them into.
W> Yes, this is what NSD does. Simple code.
W> TCP performance is not considered important, as it should rarely be
W> used with DNS. UDP performance is the goal. Therefore the
W> (otherwise excellent) patches from Aaron did not get applied, they
W> introduce extra code, portability attention, where it is not
I'd like to have a look at this patch. Maybe the patch can be worked
ina more acceptable manner. My client is very concerned about TCP
performance because of DNSSEC being on the horizon.
|David Gilbert, Independent Contractor. | Two things can be |
|Mail: dave at daveg.ca | equal if and only if they |
|http://daveg.ca | are precisely opposite. |
More information about the nsd-users