NIC/driver capabilities list?
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On the System:Advanced:Networking page, there are a bunch of checkboxes that affect the NICs:
Device polling Enable device polling Device polling is a technique that lets the system periodically poll network devices for new data instead of relying on interrupts. This prevents your webConfigurator, SSH, etc. from being inaccessible due to interrupt floods when under extreme load. Generally this is not recommended. Not all NICs support polling; see the pfSense homepage for a list of supported cards. Hardware Checksum Offloading Disable hardware checksum offload Checking this option will disable hardware checksum offloading. Checksum offloading is broken in some hardware, particularly some Realtek cards. Rarely, drivers may have problems with checksum offloading and some specific NICs. Hardware TCP Segmentation Offloading Disable hardware TCP segmentation offload Checking this option will disable hardware TCP segmentation offloading (TSO, TSO4, TSO6). This offloading is broken in some hardware drivers, and may impact performance with some specific NICs. Hardware Large Receive Offloading Disable hardware large receive offload Checking this option will disable hardware large receive offloading (LRO). This offloading is broken in some hardware drivers, and may impact performance with some specific NICs.The options are ripe with phrases like "is broken in some hardware drivers" or "may impact performance with some specific NICs", etc.
Of course, personally I'm interested in which of these options is safe to enable on my em NICs, but in general, I wonder where there's a list of NICs/drivers and the corresponding recommended settings for any given version of BSD. It's kind of silly to do in software what hardware could do, but it's even more silly to get into trouble because hardware or drivers are broken, when it could be bypassed.
Experimenting is trouble, because it may not just break, but simply cause subtle issues hard to track down, hence the question if there's any sort of list maintained about which drivers/NICs are affected by the various issues… -
I'd love to see a list like that, but I think is unlikely we'll ever have one. IMO guarantees are very uncommon in free/open source software, most likely you'll just get lots of "probably", "usually", "most" and words like that :(
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It's impossible to create such a list, those things vary even between different NICs with the same chipset (usually limited only to cheap stuff like Realtek). With em NICs, leave everything at defaults.
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Yeah, with my re NICs I got the best performance by completely disabling all offloading.
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I have Dual NIC NC360T and a onboard NIC (mainboard P5B-VM SE).
Which option should I select?
