From c98a764c681f8b70812a9f13a6e61c96aa1a69d2 Mon Sep 17 00:00:00 2001 From: Rick Macklem Date: Sat, 2 Jan 2021 16:58:43 -0800 Subject: [PATCH] cp(1): fix performance issue for large non-sparse file copies PR252358 reported a serious performance problem when copying a large non-sparse file on a UFS file system. This problem seems to have been caused by a large number of SEEK_HOLE operations, with one done for each copy_file_range(2) call. This patch modifies cp(1) to use a large (SSIZE_MAX) len argument, reducing the number of system calls and resolving the performance issue. While here, convert the type of the "rcount" from "int" to "ssize_t" so that it is consistent with that returned by both read(2) and copy_file_range(2). PR: 252358 Reviewed by: asomers Differential Revision: https://reviews.freebsd.org/D27937 --- bin/cp/utils.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/bin/cp/utils.c b/bin/cp/utils.c index 1a3b5502145a..7742b0d0a516 100644 --- a/bin/cp/utils.c +++ b/bin/cp/utils.c @@ -74,11 +74,10 @@ __FBSDID("$FreeBSD$"); */ #define BUFSIZE_SMALL (MAXPHYS) -static int +static ssize_t copy_fallback(int from_fd, int to_fd, char *buf, size_t bufsize) { - int rcount; - ssize_t wresid, wcount = 0; + ssize_t rcount, wresid, wcount = 0; char *bufp; rcount = read(from_fd, buf, bufsize); @@ -100,10 +99,10 @@ copy_file(const FTSENT *entp, int dne) static char *buf = NULL; static size_t bufsize; struct stat *fs; - ssize_t wcount; + ssize_t rcount, wcount; size_t wresid; off_t wtotal; - int ch, checkch, from_fd, rcount, rval, to_fd; + int ch, checkch, from_fd, rval, to_fd; char *bufp; #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED char *p; @@ -236,7 +235,7 @@ copy_file(const FTSENT *entp, int dne) do { if (use_copy_file_range) { rcount = copy_file_range(from_fd, NULL, - to_fd, NULL, bufsize, 0); + to_fd, NULL, SSIZE_MAX, 0); if (rcount < 0 && errno == EINVAL) { /* Prob a non-seekable FD */ use_copy_file_range = 0;