Amortize the writev syscall cost by using the writev_async socket API.
This allows the socket layer to batch writes into one system call
and also apply further optimizations such as posix's MSG_ZEROCOPY
when they are available. As part of doing so we remove the error
return in the socket layer writev_async implementation for sockets
that don't have a poll group.
Doing so eliminates the send queue processing.
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Change-Id: I5432ae322afaff7b96c22269fc06b75f9ae60b81
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/475420
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
8e8a5f7c28