I've found that using the ib_comp_wq for completion queues can add
microseconds of latency in the average case and extend tail
latencies significantly. Now that we've shaved a bunch of work out
of the server's completion handlers, it should be safe to go back to
using soft IRQ rather than ib_comp_wq, in order to gain better RTT
latencies.
---
Chuck Lever (7):
svcrdma: Eliminate allocation of recv_ctxt objects in backchannel
svcrdma: Clean up use of rdma->sc_pd->device in Receive paths
svcrdma: Pre-allocate svc_rdma_recv_ctxt objects
svcrdma: Switch Receive CQ to soft IRQ
svcrdma: Clean up use of rdma->sc_pd->device
svcrdma: Move the svcxprt_rdma::sc_pd field
svcrdma: Move Send CQ to SOFTIRQ context
include/linux/sunrpc/svc_rdma.h | 6 +--
net/sunrpc/xprtrdma/svc_rdma_backchannel.c | 11 ++--
net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 53 +++++++++++--------
net/sunrpc/xprtrdma/svc_rdma_rw.c | 4 +-
net/sunrpc/xprtrdma/svc_rdma_sendto.c | 59 ++++++++++++----------
net/sunrpc/xprtrdma/svc_rdma_transport.c | 6 +--
6 files changed, 75 insertions(+), 64 deletions(-)
--
Chuck Lever
