This patch adds an option the specify the offset of the first request made by qemu-img bench. This allows to benchmark misaligned requests.
Signed-off-by: Kevin Wolf <kw...@redhat.com> Reviewed-by: Denis V. Lunev <d...@openvz.org> --- qemu-img-cmds.hx | 4 ++-- qemu-img.c | 23 ++++++++++++++++++++--- qemu-img.texi | 5 +++-- 3 files changed, 25 insertions(+), 7 deletions(-) diff --git a/qemu-img-cmds.hx b/qemu-img-cmds.hx index baca85e..117d0f9 100644 --- a/qemu-img-cmds.hx +++ b/qemu-img-cmds.hx @@ -10,9 +10,9 @@ STEXI ETEXI DEF("bench", img_bench, - "bench [-c count] [-d depth] [-f fmt] [-n] [--pattern=pattern] [-q] [-s buffer_size] [-t cache] [-w] filename") + "bench [-c count] [-d depth] [-f fmt] [-n] [-o offset] [--pattern=pattern] [-q] [-s buffer_size] [-t cache] [-w] filename") STEXI -@item bench [-c @var{count}] [-d @var{depth}] [-f @var{fmt}] [-n] [--pattern=@var{pattern}] [-q] [-s @var{buffer_size}] [-t @var{cache}] [-w] @var{filename} +@item bench [-c @var{count}] [-d @var{depth}] [-f @var{fmt}] [-n] [-o @var{offset}] [--pattern=@var{pattern}] [-q] [-s @var{buffer_size}] [-t @var{cache}] [-w] @var{filename} ETEXI DEF("check", img_check, diff --git a/qemu-img.c b/qemu-img.c index 85d1353..480ef8d 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -3515,6 +3515,7 @@ static int img_bench(int argc, char **argv) bool is_write = false; int count = 75000; int depth = 64; + int64_t offset = 0; size_t bufsize = 4096; int pattern = 0; int64_t image_size; @@ -3532,7 +3533,7 @@ static int img_bench(int argc, char **argv) {"pattern", required_argument, 0, OPTION_PATTERN}, {0, 0, 0, 0} }; - c = getopt_long(argc, argv, "hc:d:f:nqs:t:w", long_options, NULL); + c = getopt_long(argc, argv, "hc:d:f:no:qs:t:w", long_options, NULL); if (c == -1) { break; } @@ -3570,6 +3571,19 @@ static int img_bench(int argc, char **argv) case 'n': flags |= BDRV_O_NATIVE_AIO; break; + case 'o': + { + char *end; + errno = 0; + offset = qemu_strtosz_suffix(optarg, &end, + QEMU_STRTOSZ_DEFSUFFIX_B); + if (offset < 0|| *end) { + error_report("Invalid offset specified"); + return 1; + } + break; + } + break; case 'q': quiet = true; break; @@ -3639,10 +3653,13 @@ static int img_bench(int argc, char **argv) .bufsize = bufsize, .nrreq = depth, .n = count, + .offset = offset, .write = is_write, }; - printf("Sending %d %s requests, %d bytes each, %d in parallel\n", - data.n, data.write ? "write" : "read", data.bufsize, data.nrreq); + printf("Sending %d %s requests, %d bytes each, %d in parallel " + "(starting at offset %" PRId64 ")\n", + data.n, data.write ? "write" : "read", data.bufsize, data.nrreq, + data.offset); data.buf = blk_blockalign(blk, data.nrreq * data.bufsize); memset(data.buf, pattern, data.nrreq * data.bufsize); diff --git a/qemu-img.texi b/qemu-img.texi index c477fbf..9bffad2 100644 --- a/qemu-img.texi +++ b/qemu-img.texi @@ -131,13 +131,14 @@ Skip the creation of the target volume Command description: @table @option -@item bench [-c @var{count}] [-d @var{depth}] [-f @var{fmt}] [-n] [--pattern=@var{pattern}] [-q] [-s @var{buffer_size}] [-t @var{cache}] [-w] @var{filename} +@item bench [-c @var{count}] [-d @var{depth}] [-f @var{fmt}] [-n] [-o @var{offset}] [--pattern=@var{pattern}] [-q] [-s @var{buffer_size}] [-t @var{cache}] [-w] @var{filename} Run a simple sequential I/O benchmark on the specified image. If @code{-w} is specified, a write test is performed, otherwise a read test is performed. A total number of @var{count} I/O requests is performed, each @var{buffer_size} -bytes in size, and with @var{depth} requests in parallel. +bytes in size, and with @var{depth} requests in parallel. The first request +starts at the position given by @var{offset}. If @code{-n} is specified, the native AIO backend is used if possible. On Linux, this option only works if @code{-t none} or @code{-t directsync} is -- 1.8.3.1