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>
---
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 d651674..b9b521e 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] [-q] [-s buffer_size] [-t
cache] [-w] filename")
+ "bench [-c count] [-d depth] [-f fmt] [-n] [-o offset] [-q] [-s
buffer_size] [-t cache] [-w] filename")
STEXI
-@item bench [-c @var{count}] [-d @var{depth}] [-f @var{fmt}] [-n] [-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}] [-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 142efb1..fcac8b8 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -3514,6 +3514,7 @@ 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;
int64_t image_size;
BlockBackend *blk = NULL;
@@ -3529,7 +3530,7 @@ static int img_bench(int argc, char **argv)
{"image-opts", no_argument, 0, OPTION_IMAGE_OPTS},
{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;
}
@@ -3567,6 +3568,19 @@ 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;
@@ -3625,10 +3639,13 @@ 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, 0, data.nrreq * data.bufsize);
diff --git a/qemu-img.texi b/qemu-img.texi
index 34e94db..c37380e 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] [-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}] [-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
