From 70b9829ea73931f7e2f23fbe5f1853e0dca5ca12 Mon Sep 17 00:00:00 2001 From: "barkalow@iabervon.org" Date: Tue, 2 Aug 2005 19:46:29 -0400 Subject: [PATCH] Parallelize pulling by ssh This causes ssh-pull to request objects in prefetch() and read then in fetch(), such that it reduces the unpipelined round-trip time. This also makes sha1_write_from_fd() support having a buffer of data which it accidentally read from the fd after the object; this was formerly not a problem, because it would always get a short read at the end of an object, because the next object had not been requested. This is no longer true. Signed-off-by: Daniel Barkalow Signed-off-by: Junio C Hamano --- ssh-pull.c | 41 +++++++++++++++++++++++++++++++++-------- 1 file changed, 33 insertions(+), 8 deletions(-) (limited to 'ssh-pull.c') diff --git a/ssh-pull.c b/ssh-pull.c index 4cf9b6a167..bdc99dfdc5 100644 --- a/ssh-pull.c +++ b/ssh-pull.c @@ -10,24 +10,49 @@ static int fd_out; static unsigned char remote_version = 0; static unsigned char local_version = 1; +ssize_t force_write(int fd, void *buffer, size_t length) +{ + ssize_t ret = 0; + while (ret < length) { + ssize_t size = write(fd, buffer + ret, length - ret); + if (size < 0) { + return size; + } + if (size == 0) { + return ret; + } + ret += size; + } + return ret; +} + void prefetch(unsigned char *sha1) { + char type = 'o'; + force_write(fd_out, &type, 1); + force_write(fd_out, sha1, 20); + //memcpy(requested + 20 * prefetches++, sha1, 20); } +static char conn_buf[4096]; +static size_t conn_buf_posn = 0; + int fetch(unsigned char *sha1) { int ret; signed char remote; - char type = 'o'; - if (has_sha1_file(sha1)) - return 0; - write(fd_out, &type, 1); - write(fd_out, sha1, 20); - if (read(fd_in, &remote, 1) < 1) - return -1; + + if (conn_buf_posn) { + remote = conn_buf[0]; + memmove(conn_buf, conn_buf + 1, --conn_buf_posn); + } else { + if (read(fd_in, &remote, 1) < 1) + return -1; + } + //fprintf(stderr, "Got %d\n", remote); if (remote < 0) return remote; - ret = write_sha1_from_fd(sha1, fd_in); + ret = write_sha1_from_fd(sha1, fd_in, conn_buf, 4096, &conn_buf_posn); if (!ret) pull_say("got %s\n", sha1_to_hex(sha1)); return ret; -- cgit v1.2.3