From 38b50dba4704856194ac02b98e492d2349d64058 Mon Sep 17 00:00:00 2001 From: Stefano Brivio Date: Fri, 23 Apr 2021 22:22:37 +0200 Subject: passt: Spare some syscalls, add some optimisations from profiling Avoid a bunch of syscalls on forwarding paths by: - storing minimum and maximum file descriptor numbers for each protocol, fall back to SO_PROTOCOL query only on overlaps - allocating a larger receive buffer -- this can result in more coalesced packets than sendmmsg() can take (UIO_MAXIOV, i.e. 1024), so make sure we don't exceed that within a single call to protocol tap handlers - nesting the handling loop in tap_handler() in the receive loop, so that we have better chances of filling our receive buffer in fewer calls - skipping the recvfrom() in the UDP handler on EPOLLERR -- there's nothing to be done in that case and while at it: - restore the 20ms timer interval for periodic (TCP) events, I accidentally changed that to 100ms in an earlier commit - attempt using SO_ZEROCOPY for UDP -- if it's not available, sendmmsg() will succeed anyway - fix the handling of the status code from sendmmsg(), if it fails, we'll try to discard the first message, hence return 1 from the UDP handler Signed-off-by: Stefano Brivio --- tcp.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'tcp.h') diff --git a/tcp.h b/tcp.h index da081ad..2a79a75 100644 --- a/tcp.h +++ b/tcp.h @@ -12,9 +12,13 @@ void tcp_timer(struct ctx *c, struct timespec *ts); /** * struct tcp_ctx - Execution context for TCP routines * @hash_secret: 128-bit secret for hash functions, ISN and hash table + * @fd_min: Lowest file descriptor number for TCP ever used + * @fd_max: Highest file descriptor number for TCP ever used */ struct tcp_ctx { uint64_t hash_secret[2]; + int fd_min; + int fd_max; }; #endif /* TCP_H */ -- cgit v1.2.3