Hi Laurent, Am 05.10.2010 21:15, schrieb Laurent Vivier: > During qemu-nbd run, I/O statistics can be now displayed using > the option '-a N' where N is the number of seconds between each > collect. > > The statistics diplayed are : I/O per second, kilobytes read per second, > kilobytes written per second, and the maximum values for each of them. > > Example: > > ... > 0 io/s, 0 R kB/s 0 W kB/s (29 io/s, 59 R kB/s, 0 W kB/s) > 123 io/s, 247 R kB/s 0 W kB/s (123 io/s, 247 R kB/s, 0 W kB/s) > 145 io/s, 290 R kB/s 0 W kB/s (145 io/s, 290 R kB/s, 0 W kB/s) > 383 io/s, 767 R kB/s 0 W kB/s (383 io/s, 767 R kB/s, 0 W kB/s) > 273 io/s, 547 R kB/s 0 W kB/s (383 io/s, 767 R kB/s, 0 W kB/s) > 2221 io/s, 4443 R kB/s 0 W kB/s (2221 io/s, 4443 R kB/s, 0 W kB/s) > 0 io/s, 0 R kB/s 0 W kB/s (2221 io/s, 4443 R kB/s, 0 W kB/s) > 0 io/s, 0 R kB/s 0 W kB/s (2221 io/s, 4443 R kB/s, 0 W kB/s) > ... > > Signed-off-by: Laurent Vivier <laur...@vivier.eu> > --- > nbd.c | 10 ++++++++ > nbd.h | 4 +++ > qemu-nbd.c | 68 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++- > 3 files changed, 80 insertions(+), 2 deletions(-) > > diff --git a/nbd.c b/nbd.c > index 4bf2eb7..730c514 100644 > --- a/nbd.c > +++ b/nbd.c > @@ -65,6 +65,12 @@ > > #define NBD_OPT_EXPORT_NAME (1 << 0) > > +/* for I/O statistics */ > + > +uint64_t nbd_stats_io = 0; > +uint64_t nbd_stats_read = 0; > +uint64_t nbd_stats_written = 0; > + > /* That's all folks */ > > #define read_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, true) > @@ -687,6 +693,8 @@ int nbd_trip(BlockDriverState *bs, int csock, off_t size, > uint64_t dev_offset, > switch (request.type) { > case NBD_CMD_READ: > TRACE("Request type is READ"); > + nbd_stats_io++; > + nbd_stats_read += request.len; > > if (bdrv_read(bs, (request.from + dev_offset) / 512, > data + NBD_REPLY_SIZE, > @@ -721,6 +729,8 @@ int nbd_trip(BlockDriverState *bs, int csock, off_t size, > uint64_t dev_offset, > break; > case NBD_CMD_WRITE: > TRACE("Request type is WRITE"); > + nbd_stats_io++; > + nbd_stats_written += request.len; > > TRACE("Reading %u byte(s)", request.len); > > diff --git a/nbd.h b/nbd.h > index fc3a594..2d9457b 100644 > --- a/nbd.h > +++ b/nbd.h > @@ -44,6 +44,10 @@ enum { > > #define NBD_DEFAULT_PORT 10809 > > +extern uint64_t nbd_stats_io; > +extern uint64_t nbd_stats_read; > +extern uint64_t nbd_stats_written; > + > size_t nbd_wr_sync(int fd, void *buffer, size_t size, bool do_read); > int tcp_socket_outgoing(const char *address, uint16_t port); > int tcp_socket_incoming(const char *address, uint16_t port); > diff --git a/qemu-nbd.c b/qemu-nbd.c > index 99f1d22..7626c37 100644 > --- a/qemu-nbd.c > +++ b/qemu-nbd.c > @@ -37,6 +37,7 @@ > #define NBD_BUFFER_SIZE (1024*1024) > > static int verbose; > +static int delay = 0;
I'd prefer calling this nbd_stat_delay or something. delay is relatively unspecific for a global variable. > static void usage(const char *name) > { > @@ -44,6 +45,7 @@ static void usage(const char *name) > "Usage: %s [OPTIONS] FILE\n" > "QEMU Disk Network Block Device Server\n" > "\n" > +" -a, --stats=N display statistics every N seconds\n" > " -p, --port=PORT port to listen on (default `%d')\n" > " -o, --offset=OFFSET offset into the image\n" > " -b, --bind=IFACE interface to bind to (default `0.0.0.0')\n" > @@ -180,6 +182,49 @@ static void show_parts(const char *device) > } > } > > +static void nbd_stats(void) > +{ > + static struct timespec prev; > + static int first = 1; > + static uint64_t max_read = 0, max_written = 0, max_io = 0; > + struct timespec current; > + long seconds; > + uint64_t current_read = 0, current_written = 0, current_io = 0; > + > + clock_gettime(CLOCK_MONOTONIC, ¤t); I think there was a discussion recently that clock_gettime doesn't exist everywhere. Is there a specific reason why qemu_gettimeofday() isn't good enough here? > + if (first) { > + first = 0; > + prev = current; > + return; > + } > + > + seconds = (current.tv_sec - prev.tv_sec) * 1000 + > + (current.tv_nsec - prev.tv_nsec) / 1000000; Despite the name of the variable, this looks like milliseconds. > + > + if (seconds < delay * 1000) > + return; > + > + current_io = nbd_stats_io * 1000 / seconds; > + if (current_io > max_io) > + max_io = current_io; > + current_read = nbd_stats_read * 1000 / seconds / 1024; > + if (current_read > max_read) > + max_read = current_read; > + current_written = nbd_stats_written * 1000 / seconds / 1024; > + if (current_written > max_written) > + max_written = current_written; > + > + printf("%"PRIu64" io/s, %"PRIu64" R kB/s %"PRIu64" W kB/s " > + "(%"PRIu64" io/s, %"PRIu64" R kB/s, %"PRIu64" W kB/s)\n", Maybe add a "max: " message in the brackets, so that users know what this is supposed to mean? > + current_io, current_read, current_written, > + max_io, max_read, max_written); > + > + nbd_stats_io = 0; > + nbd_stats_read = 0; > + nbd_stats_written = 0; > + prev = current; > +} Please use four spaces instead of tabs for indentation. > + > int main(int argc, char **argv) > { > BlockDriverState *bs; > @@ -195,11 +240,12 @@ int main(int argc, char **argv) > char *device = NULL; > char *socket = NULL; > char sockpath[128]; > - const char *sopt = "hVb:o:p:rsnP:c:dvk:e:t"; > + const char *sopt = "hVb:o:a:p:rsnP:c:dvk:e:t"; > struct option lopt[] = { > { "help", 0, NULL, 'h' }, > { "version", 0, NULL, 'V' }, > { "bind", 1, NULL, 'b' }, > + { "stats", 1, NULL, 'a' }, > { "port", 1, NULL, 'p' }, > { "socket", 1, NULL, 'k' }, > { "offset", 1, NULL, 'o' }, > @@ -243,6 +289,15 @@ int main(int argc, char **argv) > case 'b': > bindto = optarg; > break; > + case 'a': > + delay = strtol(optarg, &end, 0); > + if (*end) { > + errx(EXIT_FAILURE, "Invalid statistics delay `%s'", optarg); > + } > + if (delay < 0) { > + errx(EXIT_FAILURE, "Statisctics delay must be positive > `%s'", optarg); Typo in the message ("Statisctics") > + } > + break; > case 'p': > li = strtol(optarg, &end, 0); > if (*end) { > @@ -456,7 +511,16 @@ int main(int argc, char **argv) > for (i = 0; i < nb_fds; i++) > FD_SET(sharing_fds[i], &fds); > > - ret = select(max_fd + 1, &fds, NULL, NULL, NULL); > + if (delay) { > + struct timeval timeout; > + > + nbd_stats(); > + timeout.tv_sec = delay; > + timeout.tv_usec = 0; > + ret = select(max_fd + 1, &fds, NULL, NULL, &timeout); > + } else { > + ret = select(max_fd + 1, &fds, NULL, NULL, NULL); > + } With some bad luck we can end up with almost 2*delay between two outputs (request is processed with seconds = 1000 * delay - epsilon and then we wait another delay seconds). I'm not sure if we really care, though. Kevin