Re: single packet capture time w/pcap vs. recvfrom()

[Darren Reed <darrenr () reed wattle id au>]

In some email I received from Brandon Stafford, sie wrote:
[ Charset windows-1252 unsupported, converting... ]
> Hello,
>
>     I'm writing a server that captures UDP packets and, after some
> manipulation, sends the data out the serial port. Right now, I'm using
> recvfrom(), but it takes 20 ms to execute for each packet captured. I
> know that tcpdump can capture packets much faster than 20 ms/packet on
> the same computer, so I know recvfrom() is running into trouble, probably
> because of bad checksums on the packets.

What you're looking at is unlikely a recvfrom() problem but rather one of
scheduling the process - and similarly just as unlikely to disappear because
you use pcap vs a real socket.  To say that it is would imply that a process
could not deal with more than 50 UDP packets per second ... something I find
hard to believe of any modern computer.

Darren
-
This is the tcpdump-workers list.
Visit https://lists.sandelman.ca/ to unsubscribe.