From: o.evistel@xxxxxxx > Sent: 13 July 2022 13:59 > > I am using linux-sctp as transport for SIGTRAN M3UA on RHEL 8.4 and I am > using sctp_sendmsg() and sctp_recvmsg() to send/receive. > I would like to know if the use of sctp_sendv() and sctp_recvv() enhances performances ? Every copy to/from a user buffer has a small (but measurable) cost. So anything with an iov[] array is a bit slower than an equivalent call that only has a single buffer. This is measurable when comparing sendmsg() and sendto() on (say) a UDP socket. OTOH it is all probably noise unless you are trying to send/receive 'silly numbers' of messages. Reducing the number of system calls may help. But the cost of recvmmsg() checking for a second message is significantly greater than using epoll(). So unless you actually expect lots of messages it probably isn't worth using. Assuming you have disabled Nagle, then the biggest performance gain will be from setting MSG_MORE when you know you have another message to send. Without that pretty much every M3UA message ends up in its own ethernet packet. You don't mention why you think you have a performance issue in SCTP. I think we got 40000 reflects/sec from a tcap application over M3UA and SCTP last time I measured out stack. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
