On Fri, Oct 21, 2011 at 4:16 PM, Julien Vermillard <jvermill...@gmail.com>wrote:
> On Fri, Oct 21, 2011 at 2:31 PM, Alex Karasulu <akaras...@apache.org> > wrote: > > On Fri, Oct 21, 2011 at 2:12 PM, Emmanuel Lecharny <elecha...@gmail.com > >wrote: > > > >> On 10/21/11 12:56 PM, Zigor Salvador wrote: > >> > >>> Comments after using Wireshark to sniff on the packets being sent: > >>> > >>> On 20 Oct 2011, at 16:10, Emmanuel Lecharny wrote: > >>> > >>> Each message sent and received on ethernet will use 1500 bytes, even > if > >>>> you transmit only one byte of data. > >>>> > >>> This is not correct. > >>> > >>> Using MINA's "no delay" option and sending around 439 bytes of data the > >>> Ethernet frame captured by Wireshark reports a total frame length of > 505 > >>> bytes. > >>> > >> > >> That does not change the fact that Ethernet frames are 1500 bytes > long... > >> > >> > >>> (505 = 6 (MAC) + 6 (MAC) + 2 (Type) + 20 (IP header) + 32 (TCP header) > + > >>> 439 (data)) > >>> > >>> If I enable Nagle's algorithm, several messages get crammed into a > single > >>> ethernet frame (up to the aforementioned MTU value). > >>> > >> Nagle algorithm is not a good idea for small messages, as you will have > a > >> delay between each messages, the system waiting for some more bytes to > fill > >> the PDU as much as it can before sending it to the client. > >> > >> It's usefull when sending big data, though. > >> > >> > > Wondering if MINA can get a little smarter. Just a brain dump here .... > what > > if you know according to the protocol that you're going to get a certain > > train of responses. Maybe there's a way to buffer and dump to fill to MTU > > capacity? > > > > -- > > Best Regards, > > -- Alex > > > It's not a kernel level matter ? to fill the packet to MTU limit using > Naggle ? > Yes it is however if MINA at higher levels can pump more into the buffer WITHOUT Naggle then you have a greater chance at filling to MTU. Was just wondering if anticipating in advance what a response would look like might help devise smarter buffering that leads to filling to MTU. I might be pulling this out of my arse here .. as I said it's just a brain dump. Maybe we're already doing as much as we possibly can. -- Best Regards, -- Alex
