Quad Channel Memory



  • Hello everyone,

    I was just wondering if PFsense benefits from using quad channel memory.

    My hardware:

    Super A1SRi-2758F 8 core atom processor
    intel x540t2 nic
    currently single channel 8gb ram. I was gonna upgrade to quad channel 32gb ram
    120gb samsung ssd

    the router is connected to the ubiquiti us16xg 10gb switch

    I saw on another forum post that 10gb uses more ram as buffer between nic and cpu.

    thanks for your help guys! have a great evening.

    David Tiao



  • I'm an idoit. system only has 2 channels :D

    but for future reference. does more ram channels benefit 10gb networking?



  • Well…

    DDR4 RAM basically has no problems getting multiple of tens of gigabits per second, so more channels don't immediately help. Say you want to do a lot of processing on the packets and have 4 or more 10GbE interfaces, then it might help.



  • From a theoretical standpoint, depending on the IO pattern, more channels could help by reducing latency. I'm not sure if this happens or if there's an inflection point where it changes from doesn't to does.



  • I was just wondering if PFsense benefits from using quad channel memory.

    Not alone from that and at second not only based on the channels! But, if your CPU is able to push
    an amount of network load and your memory system (RAM) gets saturated you will be able to limited by
    that let us call it slower RAM modules. So if your RAM will be fu**ing fast and your are installing more
    then one of the common available packets for pfSense is makes also sense to have much RAM inside of
    your pfSense box. As an example we talk about an installation likes, pfSense, Squid, SquidGuard, SARG,
    Snort, pfBlockerNG & DNSBL + TLD ClamAV and perhaps a/dpinger on top, this might be good to be right
    sorted with enough RAM. Because if you then will (perhaps);

    • high up the mbuf size
    • shorten down the network queues
    • high up the Squid (default) RAM limit
    • setting up in pfBlockerNG many lists for many IP addresses
      and so on and so on, so you might be happy with much RAM too. Fast enough it should be for the most
      things because all will be running through the memory system and this should be not saturated at all.

    My hardware:
    Super A1SRi-2758F 8 core atom processor
    intel x540t2 nic
    currently single channel 8gb ram. I was gonna upgrade to quad channel 32gb ram
    120gb samsung ssd

    If you will install pfBlockerNG & DNSBL + TLD it might be a good choice but if not the amount of RAM is
    perhaps to high, and 16 GB will be then more then enough, also if you increase the amount of the mbuf size.

    the router is connected to the ubiquiti us16xg 10gb switch

    To the DMZ and or to the LAN side this might be a fine think.

    I saw on another forum post that 10gb uses more ram as buffer between nic and cpu.

    It is pending on the used NICs and the used driver for that cards, I have seen and read about that some
    users where shorten down the amount of mbuf size to 65000 (broadcom cards (NICs)) and for Intel cards
    nearly 1000000 was the best option there fore but also together with shorten down the amount of network
    queues too!

    2 GB normal usage
    4 GB normal, snort and Squid
    8 GB normal, snort, Squid, VPN and high up the mbuf size
    16 GB normal, snort, Squid, VPN and high up the mbuf size plus pfBlockerNG
    32 GB normal, snort, Squid, VPN and high up the mbuf size plus pfBlockerNG & DNSBL + TLD (intensive)