[CentOS] Performance of CentOS as a NAT gateway

Mon Sep 10 23:24:45 UTC 2007
John R Pierce <pierce at hogranch.com>

Bart Schaefer wrote:
> On 9/10/07, Bart Schaefer <barton.schaefer at gmail.com> wrote:
>> On 9/10/07, Guy Boisvert <boisvert.guy at videotron.ca> wrote:
>>> On top of that, i'd say that a PC, with whatever processor you could
>>> put, is able to service a certain amount of interrupts / second.
>> # cat /proc/interrupts
> Ok, so obviously just that snapshot wasn't very useful, sorry.
> Several minutes of "vmstat 2" output indicates that the number of
> interrupts per second on the NAT gateway ranges between 600 and 1200,
> occasionally as low as 540 or as high as 1300.
> (Working on getting wireshark in a place where we can monitor both ends.)

wireshark can process and display packet capture files from tcpdump -w 
filename, or most any other packet capture utility, as well as capture 
data itself.

capture a few megabytes of packets on the appropriate interface of the 
firewall, then transfer them to a workstation with Wireshark for analysis.