diff --git a/io/iob_send.c b/io/iob_send.c index 4ccbe92..30ed8b8 100644 --- a/io/iob_send.c +++ b/io/iob_send.c @@ -127,6 +127,9 @@ int64 iob_send(int64 s,io_batch* b) { int64 sent; long i; long headers; +#ifdef MSG_MORE + int docork; +#endif #ifdef HAVE_BSDSENDFILE long trailers; #endif @@ -188,6 +191,45 @@ eagain: } } #else + /* Linux has two ways to coalesce sent data; either setsockopt + * TCP_CORK or sendto/sendmsg with MSG_MORE. MSG_MORE saves syscalls + * in one scenario: when there is n buffers and then possibly one + * file to send. If there is more buffers after the file, then we + * need to use TCP_CORK to prevent the TCP push after the file. */ +#ifdef MSG_MORE + if (e+i==last) + docork=-1; /* no files, only buffer, so no need for TCP_CORK or MSG_MORE */ + else + docork=!(e+i+1==last); + if (docork>0) + setsockopt(s,IPPROTO_TCP,TCP_CORK,(int[]){ 1 },sizeof(int)); + if (headers) { + if (docork<0) { /* write+writev */ + if (headers==1) /* cosmetics for strace */ + sent=write(s,v[0].iov_base,v[0].iov_len); + else + sent=writev(s,v,headers); + } else { + if (headers==1) /* cosmetics for strace */ + sent=sendto(s,v[0].iov_base,v[0].iov_len,MSG_MORE, NULL, 0); + else { + struct msghdr msg; + memset(&msg,0,sizeof(msg)); + msg.msg_iov=v; + msg.msg_iovlen=headers; + sent=sendmsg(s,&msg,MSG_MORE); + } + } + if (sent==-1) { + if (errno==EAGAIN) { + io_eagain_write(s); + return -1; + } + sent=-3; + } + } else + sent=io_sendfile(s,e->fd,e->offset,e->n); +#else /* !MSG_MORE */ #ifdef TCP_CORK if (b->bufs && b->files && !b->next) { static int one=1; @@ -208,16 +250,23 @@ eagain: } } else sent=io_sendfile(s,e->fd,e->offset,e->n); +#endif /* !MSG_MORE */ #endif if (sent>0) total+=sent; else return total?total:(uint64)sent; if ((uint64)sent==b->bytesleft) { +#ifdef MSG_MORE + if (docork==1) { +#endif #ifdef TCP_CORK - if (b->bufs && b->files) { - static int zero=0; - setsockopt(s,IPPROTO_TCP,TCP_CORK,&zero,sizeof(zero)); + if (b->bufs && b->files) { + static int zero=0; + setsockopt(s,IPPROTO_TCP,TCP_CORK,&zero,sizeof(zero)); + } +#endif +#ifdef MSG_MORE } #endif iob_reset(b); diff --git a/test/iob.c b/test/iob.c index d12fa76..a2c6b1c 100644 --- a/test/iob.c +++ b/test/iob.c @@ -17,9 +17,12 @@ int main() { assert(iob_addbuf(b,"Huhu",4)); assert(iob_addbuf(b," fnord\n",7)); assert(iob_addfile(b,fd,10,10)); + iob_send(1,b); +#if 0 do { r=iob_write(1,b,write_cb); } while (r>0); +#endif iob_free(b); return 0; }