PfSense with PAE kernel

  • Thanks for Your help!

  • It would probably be useful to explain why you think a PAE kernel would be useful for pfSense.

    PAE is a solution to some problems but not a solution for others.

  • Well, sometimes happen to setup systems with more than 4 GB of RAM (old servers recycled to Firewall, IDS, LoadBalancing and more…), with many different connection (and not only the standard WAN/LAN settings).
    The default messages of system is, in this cases: I'm ignoring everything over 4GB... Sorry!

  • Depending on the chipset and BIOS the non-PAE kernel can generally address about 3GB of physical memory. (The remainder of the 4GB physical address space is 'reserved' for addressing CPU registers, PCI device memory address space etc.)

    The message about memory above 4GB being ignored should be treated as an informational message rather than an error message. If it troubles people just remove some of the RAM (and possibly reuse it in another system).

    Using a PAE kernel will not make any more memory available for kernel data structures such as firewall rules, state tables, routes etc but it will make more memory available to hold applications in memory (possibly reducing swapping and paging). Therefore I suspect that for most pfSense users a PAE kernel would be of no substantial benefit.