Mellanox Adapters - Comparison Table

Version 16

    This post shows the main differences and feature support on the latest Mellanox adapters.

    This post is basic and aimed for FAE and IT managers.




    ClassFeatureConnectX-3ConnectX-3 ProConnectX-4 LxConnectX-4Connect-IBReferences and Notes
    InterfacePCIex8 Gen3x8 Gen3x8 Gen3x8, x16 Gen3x8, x16 Gen3
    InterfacePort/Speed options2 ports of 10/40/56GbE2 ports of 10/40/56GbE

    2 ports of 10/25GbE

    1 port of 40/50GbE

    2 ports of 100/56/50/40/25/10GbE2 ports of FDR InfinBandNote: There various of adapter cards. Some OPNs for example could be speed limited, e.g.ConnectX-4 FDR (that won’t link up EDR) or Connect-IB that is x8 only and not x16.
    InterfaceCoherent Accelerator Processor Interface (CAPI)---SupportedN/A

    IBM - Coherent Accelerator Processor Interface (CAPI)





    RDMA/RoCE Solutions

    Note: ConnectX-4 Lx is Ethernet only (RoCE) while Connect-IB is InfiniBand only (RDMA).

    RDMA and RoCERoCE Congestion Control-SupportedSupportedSupportedN/A

    RDMA/RoCE Solutions

    Understanding RoCEv2 Congestion Management

    RoCEv2 CNP Packet Format Example

    HowTo Configure RoCE Congestion Control for Windows 2012

    HPCCore DirectSupportedSupportedSupportedSupportedSupported

    Exploited by FCA and extended by Mellanox SHARP technology.


    GPU Direct Uses PeerDirect.


    Dynamically Connected Transport (DCT)--SupportedSupportedSupported
    CPU OffloadsStateless Ethernet offloadSupportedSupportedSupported (LRO, LSOv2)Supported (LRO, LSOv2)N/A

    LRO standard for Large Receive Offload. it increases inbound throughput of high-bandwidth network connections by reducing CPU overhead. It works by aggregating multiple incoming packets from a single stream into a larger buffer before they are passed higher up the networking stack, thus reducing the number of packets that have to be processed. LRO is available in kernel versions < 3.1 for untagged traffic.


    LSO stands for Large Send offload.


    See MLNX_OFED User Manual for more info.

    CPU OffloadsRSS (MAC, VLAN 5 Tuple)SupportedSupportedSupported +Supported +N/AHowTo Configure RSS on ConnectX-3 Pro for Windows 2012 server
    VirtualizationSR-IOVSupportedSupportedSupportedSupportedSupportedVirtualization Solutions
    VirtualizationMulti Host---SupportedN/A

    Overlay Network


    Hardware offload-SupportedSupportedSupportedN/AVirtualization Solutions

    Overlay Network


    Encap/Decap--SupportedSupportedN/AThe difference here between ConnectX-3 Pro and ConnectX-4 is that the Encapsulation and Decapsulation for the overlay protocol (e.g. VXLAN/NVGRE) is done in HW in case of ConnectX-4.
    StorageErasure Coding Offload--SupportedSupportedN/A

    Reed Solomon Erasure Coding hardware offload is supported by the adapters.

    Verbs API are available.

    Understanding Erasure Coding Offload

    StorageT10/DIF Signature Handover---SupportedSupportedHowTo Enable T10-PI (T10-DIF) Data Integrity Protection in iSER with LIO Target
    Cloud IntegrationMirantis Fuel

    Supported Fuel 7.0/8.0

    Supported Fuel 7.0/8.0Supported Fuel 8.0Supported Fuel 8.0

    Cloud Solutions