CPU power required for gigabit?

  • I have outgrown my low powered geo cpu fw, now that my isp has given me 10mbs/0.5mbs. CPU peaks at 50% with internet traffic. DMZ to LAN traffic absolutely kills it. I get no more than 2.2Mb (megabytes) per second with CPU at 100%.

    I have a gigabit SMC switch that is supposed to be able to handle jumbo packets and a collection of Intel MT1000 single and dual NICs.

    My question is what speed CPU do I need to make sure it isn't the bottle neck ?
    I don't really want to throw in a 3Ghz dual core cpu when a 1.5Ghz Pentium4 will do the job with plenty to spare.

    Assuming it is on a

    1. standard 33Mhz, 32bit  PCI bus.
    2. A 66Mhz 64bit PCIX bus.

    With 2 x 100Mbs and 2 x 1000Mbs

    Is there a chipset I should avoid or a chipset to go for, for maximum bus peformance ?

    Also how do I go about setting the packet size on the fw nics ?


  • Avoid the marvel chipsets, they have a real hit-or-miss problem with stability. Realtek always work but tend to have throughput problems.

    What is your current firewall?

    We used a Dell 4100(1ghz w/512 ram) to hold up a 45/45meg pipe for awhile….only did sustained 3-4meg tho as most of the primary servers were down for maintenance.

  • its a nokia120 running monowall 1.21

    it'd be great to have 1Gbs wirespeed, but I don't have the money for that: 10-20Mb s would do.

    I'd like to know what the optimum CPU speed and RAM to max out a PCI (32bit, 33Mhz) system and if I can get hold of another mb with PCI-X slots, then the CPU speed to max that out.

    Would pfsense use a 2nd processor effectively ?

  • The more I think about it I don't think gig-nics are the solution to the problem. Just a box with more processing power and ram. See if you can find a P3 933mhz or faster with 256 or more ram with a pair of intel managed 100meg nics or some 3com 905b/c series cards(or better).

  • Currently wraps (266mhz) will push around 32 megabit.  So anything beyond a 500 mhz box with GOOD nics should be fine.

    By GOOD I mean Intel or something as nice.