Hi! On 10:56 Wed 22 Apr , Devesh Sharma wrote: > On Tue, Apr 21, 2009 at 9:48 PM, Michael Blizek > <michi1@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > Hi! > > > > On 18:37 Tue 21 Apr , Devesh Sharma wrote: > >> Hello michi, Sorry for late reply. comments are inline: ... > >> > "ping -f -s 4096" say? How much does the latency increase if you send > >> > bigger packets? Is there a "magic value" which causes a "sudden increase" > >> > (e.g. 4051 is much slower than 4050)? > >> Yes there is a magic number for packet size of 4040 bytes in ping -s > >> 4040 gives proper results > >> but of ping -s 4041 every alternate packet get delayed upto 1000 ms. > > IP header is 20 byte > > UDP header is 8 byte (what prococol are you using?) > > I am using TCP not UDP OK. ... > I have also checked with my device debugging tool, it posting exactly > 2 descriptors each of 2048 size for every 4040 byte ping packet, so > for (4096-4040) = 56 additional bytes. This sounds interesting. Can you install a sniffer and see what is going on: - There should be 3 data packets for 4041 byte packets - Are these 3 packets sent at once or is the 3rd packet delayed until an ack is received? - Is the ack received fast or is there some delay? If a data packet has the push flag set, there should not be any delay beyond the normal network latency. - Are there any retransmissions? netstat -s may also have some hints. Can you send the values of these files in /proc/sys/net/ipv4/ ? tcp_congestion_control tcp_reordering tcp_rmem tcp_wmem > I am also not able to receive jeffrey's posts!! Have you subscribed the list? jeffrey sent his mails only to the list and has not put you in to or cc while most others have. If you are not subscribed, you can still send to the list and see replies where people have put you in to or cc. -Michi -- programing a layer 3+4 network protocol for mesh networks see http://michaelblizek.twilightparadox.com -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
