thanks for taking a look and commenting. On Sun, Jan 20, 2019 at 7:42 PM Tom Talpey <tom@xxxxxxxxxx> wrote: > > On 1/15/2019 3:53 AM, Alex Rosenbaum wrote: > > RoCE v2.0 UDP source port is used to provide per-conversation > > entropy for Network Routers (ECMP), load balancers and 802.3ad Link > > Aggregation Switching that are not aware of RoCE headers. > > > > We will use the following hash functions definition to calculate the > > RoCE UDP src_port according to the service type (QP Type) and Service ID > > (SID), or according to the source and destination QPN values where CM > > services are not used. > > Won't this result in the source port being the same for all connections > to a given remote service? In other words, all NFS/RDMA connections to a > given server will have the same src_port, and therefore will all stack > up in the same router queues? Similarly for SMB, iSER, etc. > It's true that the Remote Service ID (mapped to a DstPort) is the same for all connections. But the local bounded port (SrcPort) of CM, for each connection will be different. Each RC QP, will have its separate CM 'initiator' handle, which will have a seperate local bounded src port. You can see in the below hash calc for CM based traffic, that the SrcPort (local bound CM port) is used in the hash, so that multiple connection to the same remote will result is scattered UDP.src_prot values. > Extract the following fields from the CM IP REQ: > CM_REQ.ServiceID.DstPort [2 Bytes] > CM_REQ.PrivateData.SrcPort [2 Bytes] > RoCE.UDP.src_port = (DstPort[0..1] XOR SrcPort[0..1]) OR 0xC000 Alex
