* [PATCH v4] engines: Add Network Block Device (NBD) support using libnbd.
@ 2019-08-02 15:32 Richard W.M. Jones
2019-08-02 15:32 ` Richard W.M. Jones
0 siblings, 1 reply; 5+ messages in thread
From: Richard W.M. Jones @ 2019-08-02 15:32 UTC (permalink / raw)
To: fio; +Cc: eblake, axboe
v3 (the synchronous version) was posted earlier today. It looks like
it's not available in the online archives yet.
This is v4 which implements full asynchronous support and in my
testing is about 4-5 times faster.
Rich.
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH v4] engines: Add Network Block Device (NBD) support using libnbd.
2019-08-02 15:32 [PATCH v4] engines: Add Network Block Device (NBD) support using libnbd Richard W.M. Jones
@ 2019-08-02 15:32 ` Richard W.M. Jones
2019-08-02 15:40 ` Jens Axboe
2019-08-03 15:10 ` Sitsofe Wheeler
0 siblings, 2 replies; 5+ messages in thread
From: Richard W.M. Jones @ 2019-08-02 15:32 UTC (permalink / raw)
To: fio; +Cc: eblake, axboe
This commit adds a new engine for testing Network Block Devices
directly. It requires libnbd (https://github.com/libguestfs/libnbd).
To see how to test nbdkit or qemu-nbd read examples/nbd.fio.
Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
---
HOWTO | 2 +
Makefile | 6 +
configure | 27 ++++
engines/nbd.c | 368 +++++++++++++++++++++++++++++++++++++++++++++++
examples/nbd.fio | 35 +++++
fio.1 | 3 +
optgroup.c | 4 +
optgroup.h | 2 +
options.c | 3 +
9 files changed, 450 insertions(+)
diff --git a/HOWTO b/HOWTO
index 81244064..955ea43c 100644
--- a/HOWTO
+++ b/HOWTO
@@ -1998,6 +1998,8 @@ I/O engine
requests for IME. FIO will then decide when to commit these requests.
**libiscsi**
Read and write iscsi lun with libiscsi.
+ **nbd**
+ Synchronous read and write a Network Block Device (NBD).
I/O engine specific parameters
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/Makefile b/Makefile
index d7e5fca7..fe02bf1d 100644
--- a/Makefile
+++ b/Makefile
@@ -65,6 +65,12 @@ ifdef CONFIG_LIBISCSI
SOURCE += engines/libiscsi.c
endif
+ifdef CONFIG_LIBNBD
+ CFLAGS += $(LIBNBD_CFLAGS)
+ LIBS += $(LIBNBD_LIBS)
+ SOURCE += engines/nbd.c
+endif
+
ifdef CONFIG_64BIT
CFLAGS += -DBITS_PER_LONG=64
endif
diff --git a/configure b/configure
index a0692d58..b11b2dce 100755
--- a/configure
+++ b/configure
@@ -149,6 +149,7 @@ disable_pmem="no"
disable_native="no"
march_set="no"
libiscsi="no"
+libnbd="no"
prefix=/usr/local
# parse options
@@ -207,6 +208,8 @@ for opt do
;;
--enable-libiscsi) libiscsi="yes"
;;
+ --enable-libnbd) libnbd="yes"
+ ;;
--disable-tcmalloc) disable_tcmalloc="yes"
;;
--help)
@@ -245,6 +248,7 @@ if test "$show_help" = "yes" ; then
echo "--disable-native Don't build for native host"
echo "--with-ime= Install path for DDN's Infinite Memory Engine"
echo "--enable-libiscsi Enable iscsi support"
+ echo "--enable-libnbd Enable libnbd (NBD engine) support"
echo "--disable-tcmalloc Disable tcmalloc support"
exit $exit_val
fi
@@ -2014,6 +2018,23 @@ if test "$libiscsi" = "yes" ; then
fi
print_config "iscsi engine" "$libiscsi"
+##########################################
+# Check if we have libnbd (for NBD support).
+minimum_libnbd=0.9.6
+if test "$libnbd" = "yes" ; then
+ if $(pkg-config --atleast-version=$minimum_libnbd libnbd); then
+ libnbd="yes"
+ libnbd_cflags=$(pkg-config --cflags libnbd)
+ libnbd_libs=$(pkg-config --libs libnbd)
+ else
+ if test "$libnbd" = "yes" ; then
+ echo "libnbd" "Install libnbd >= $minimum_libnbd"
+ fi
+ libnbd="no"
+ fi
+fi
+print_config "NBD engine" "$libnbd"
+
##########################################
# Check if we have lex/yacc available
yacc="no"
@@ -2698,6 +2719,12 @@ if test "$libiscsi" = "yes" ; then
echo "LIBISCSI_CFLAGS=$libiscsi_cflags" >> $config_host_mak
echo "LIBISCSI_LIBS=$libiscsi_libs" >> $config_host_mak
fi
+if test "$libnbd" = "yes" ; then
+ output_sym "CONFIG_LIBNBD"
+ echo "CONFIG_LIBNBD=m" >> $config_host_mak
+ echo "LIBNBD_CFLAGS=$libnbd_cflags" >> $config_host_mak
+ echo "LIBNBD_LIBS=$libnbd_libs" >> $config_host_mak
+fi
cat > $TMPC << EOF
int main(int argc, char **argv)
{
diff --git a/engines/nbd.c b/engines/nbd.c
new file mode 100644
index 00000000..399da5f3
--- /dev/null
+++ b/engines/nbd.c
@@ -0,0 +1,368 @@
+/*
+ * NBD engine
+ *
+ * IO engine that talks to an NBD server.
+ *
+ * Copyright (C) 2019 Red Hat Inc.
+ * Written by Richard W.M. Jones <rjones@redhat.com>
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <errno.h>
+
+#include <libnbd.h>
+
+#include "../fio.h"
+#include "../optgroup.h"
+
+/* Actually this differs across servers, but for nbdkit ... */
+#define NBD_MAX_REQUEST_SIZE (64 * 1024 * 1024)
+
+/* Storage for the NBD handle. */
+struct nbd_data {
+ struct nbd_handle *nbd;
+ int debug;
+
+ /* The list of completed io_u structs. */
+ struct io_u **completed;
+ size_t nr_completed;
+};
+
+/* Options. */
+struct nbd_options {
+ void *padding;
+ char *uri;
+};
+
+static struct fio_option options[] = {
+ {
+ .name = "uri",
+ .lname = "NBD URI",
+ .help = "Name of NBD URI",
+ .category = FIO_OPT_C_ENGINE,
+ .group = FIO_OPT_G_NBD,
+ .type = FIO_OPT_STR_STORE,
+ .off1 = offsetof(struct nbd_options, uri),
+ },
+ {
+ .name = NULL,
+ },
+};
+
+/* Alocates nbd_data. */
+static int nbd_setup(struct thread_data *td)
+{
+ struct nbd_data *nbd_data;
+ struct nbd_options *o = td->eo;
+ struct fio_file *f;
+ int r;
+ int64_t size;
+
+ nbd_data = calloc(1, sizeof(*nbd_data));
+ if (!nbd_data) {
+ td_verror(td, errno, "calloc");
+ return 1;
+ }
+ td->io_ops_data = nbd_data;
+
+ /* Pretend to deal with files. See engines/rbd.c */
+ if (!td->files_index) {
+ add_file(td, "nbd", 0, 0);
+ td->o.nr_files = td->o.nr_files ? : 1;
+ td->o.open_files++;
+ }
+ f = td->files[0];
+
+ nbd_data->nbd = nbd_create();
+ if (!nbd_data->nbd) {
+ log_err("fio: nbd_create: %s\n", nbd_get_error());
+ return 1;
+ }
+
+ /* Get the debug flag which can be set through LIBNBD_DEBUG=1. */
+ nbd_data->debug = nbd_get_debug(nbd_data->nbd);
+
+ /* Connect synchronously here so we can check for the size and
+ * in future other properties of the server.
+ */
+ if (!o->uri) {
+ log_err("fio: nbd: uri parameter was not specified\n");
+ return 1;
+ }
+ r = nbd_connect_uri(nbd_data->nbd, o->uri);
+ if (r == -1) {
+ log_err("fio: nbd_connect_uri: %s\n", nbd_get_error());
+ return 1;
+ }
+ size = nbd_get_size(nbd_data->nbd);
+ if (size == -1) {
+ log_err("fio: nbd_get_size: %s\n", nbd_get_error());
+ return 1;
+ }
+
+ f->real_file_size = size;
+
+ nbd_close (nbd_data->nbd);
+ nbd_data->nbd = NULL;
+
+ return 0;
+}
+
+/* Closes socket and frees nbd_data -- the opposite of nbd_setup. */
+static void nbd_cleanup(struct thread_data *td)
+{
+ struct nbd_data *nbd_data = td->io_ops_data;
+
+ if (nbd_data) {
+ if (nbd_data->nbd)
+ nbd_close(nbd_data->nbd);
+ free(nbd_data);
+ }
+}
+
+/* Connect to the server from each thread. */
+static int nbd_init(struct thread_data *td)
+{
+ struct nbd_options *o = td->eo;
+ struct nbd_data *nbd_data = td->io_ops_data;
+ int r;
+
+ if (!o->uri) {
+ log_err("fio: nbd: uri parameter was not specified\n");
+ return 1;
+ }
+
+ nbd_data->nbd = nbd_create();
+ if (!nbd_data->nbd) {
+ log_err("fio: nbd_create: %s\n", nbd_get_error());
+ return 1;
+ }
+ /* This is actually a synchronous connect and handshake. */
+ r = nbd_connect_uri(nbd_data->nbd, o->uri);
+ if (r == -1) {
+ log_err("fio: nbd_connect_uri: %s\n", nbd_get_error());
+ return 1;
+ }
+
+ log_info("fio: connected to NBD server\n");
+ return 0;
+}
+
+/* A command in flight has been completed. */
+static int cmd_completed (unsigned valid_flag, void *vp, int *error)
+{
+ struct io_u *io_u;
+ struct nbd_data *nbd_data;
+ struct io_u **completed;
+
+ if (!(valid_flag & LIBNBD_CALLBACK_VALID))
+ return 0;
+
+ io_u = vp;
+ nbd_data = io_u->engine_data;
+
+ if (nbd_data->debug)
+ log_info("fio: nbd: command completed\n");
+
+ if (*error != 0)
+ io_u->error = *error;
+ else
+ io_u->error = 0;
+
+ /* Add this completion to the list so it can be picked up
+ * later by ->event.
+ */
+ completed = realloc(nbd_data->completed,
+ sizeof(struct io_u *) *
+ (nbd_data->nr_completed+1));
+ if (completed == NULL) {
+ io_u->error = errno;
+ return 0;
+ }
+
+ nbd_data->completed = completed;
+ nbd_data->completed[nbd_data->nr_completed] = io_u;
+ nbd_data->nr_completed++;
+
+ return 0;
+}
+
+/* Begin read or write request. */
+static enum fio_q_status nbd_queue(struct thread_data *td,
+ struct io_u *io_u)
+{
+ struct nbd_data *nbd_data = td->io_ops_data;
+ int r;
+
+ fio_ro_check(td, io_u);
+
+ io_u->engine_data = nbd_data;
+
+ if (io_u->ddir == DDIR_WRITE || io_u->ddir == DDIR_READ)
+ assert(io_u->xfer_buflen <= NBD_MAX_REQUEST_SIZE);
+
+ switch (io_u->ddir) {
+ case DDIR_READ:
+ r = nbd_aio_pread_callback(nbd_data->nbd,
+ io_u->xfer_buf, io_u->xfer_buflen,
+ io_u->offset,
+ cmd_completed, io_u,
+ 0);
+ break;
+ case DDIR_WRITE:
+ r = nbd_aio_pwrite_callback(nbd_data->nbd,
+ io_u->xfer_buf, io_u->xfer_buflen,
+ io_u->offset,
+ cmd_completed, io_u,
+ 0);
+ break;
+ case DDIR_TRIM:
+ r = nbd_aio_trim_callback(nbd_data->nbd, io_u->xfer_buflen,
+ io_u->offset,
+ cmd_completed, io_u,
+ 0);
+ break;
+ case DDIR_SYNC:
+ /* XXX We could probably also handle
+ * DDIR_SYNC_FILE_RANGE with a bit of effort.
+ */
+ r = nbd_aio_flush_callback(nbd_data->nbd,
+ cmd_completed, io_u,
+ 0);
+ break;
+ default:
+ io_u->error = EINVAL;
+ return FIO_Q_COMPLETED;
+ }
+
+ if (r == -1) {
+ /* errno is optional information on libnbd error path;
+ * if it's 0, set it to a default value
+ */
+ io_u->error = nbd_get_errno();
+ if (io_u->error == 0)
+ io_u->error = EIO;
+ return FIO_Q_COMPLETED;
+ }
+
+ if (nbd_data->debug)
+ log_info("fio: nbd: command issued\n");
+ io_u->error = 0;
+ return FIO_Q_QUEUED;
+}
+
+static unsigned retire_commands(struct nbd_handle *nbd)
+{
+ int64_t cookie;
+ unsigned r = 0;
+
+ while ((cookie = nbd_aio_peek_command_completed(nbd)) > 0) {
+ /* Ignore the return value. cmd_completed has already
+ * checked for an error and set io_u->error. We only
+ * have to call this to retire the command.
+ */
+ nbd_aio_command_completed(nbd, cookie);
+ r++;
+ }
+
+ if (nbd_get_debug(nbd))
+ log_info("fio: nbd: %u commands retired\n", r);
+ return r;
+}
+
+static int nbd_getevents(struct thread_data *td, unsigned int min,
+ unsigned int max, const struct timespec *t)
+{
+ struct nbd_data *nbd_data = td->io_ops_data;
+ int r;
+ unsigned events = 0;
+ int timeout;
+
+ /* XXX This handling of timeout is wrong because it will wait
+ * for up to loop iterations * timeout.
+ */
+ timeout = !t ? -1 : t->tv_sec * 1000 + t->tv_nsec / 1000000;
+
+ while (events < min) {
+ r = nbd_poll(nbd_data->nbd, timeout);
+ if (r == -1) {
+ /* error in poll */
+ log_err("fio: nbd_poll: %s\n", nbd_get_error());
+ return -1;
+ }
+ else {
+ /* poll made progress */
+ events += retire_commands(nbd_data->nbd);
+ }
+ }
+
+ return events;
+}
+
+static struct io_u *nbd_event(struct thread_data *td, int event)
+{
+ struct nbd_data *nbd_data = td->io_ops_data;
+
+ if (nbd_data->nr_completed == 0)
+ return NULL;
+
+ /* XXX We ignore the event number and assume fio calls us
+ * exactly once for [0..nr_events-1].
+ */
+ nbd_data->nr_completed--;
+ return nbd_data->completed[nbd_data->nr_completed];
+}
+
+static int nbd_io_u_init(struct thread_data *td, struct io_u *io_u)
+{
+ io_u->engine_data = NULL;
+ return 0;
+}
+
+static void nbd_io_u_free(struct thread_data *td, struct io_u *io_u)
+{
+ /* Nothing needs to be done. */
+}
+
+static int nbd_open_file(struct thread_data *td, struct fio_file *f)
+{
+ return 0;
+}
+
+static int nbd_invalidate(struct thread_data *td, struct fio_file *f)
+{
+ return 0;
+}
+
+static struct ioengine_ops ioengine = {
+ .name = "nbd",
+ .version = FIO_IOOPS_VERSION,
+ .options = options,
+ .option_struct_size = sizeof(struct nbd_options),
+ .flags = FIO_DISKLESSIO | FIO_NOEXTEND,
+
+ .setup = nbd_setup,
+ .init = nbd_init,
+ .cleanup = nbd_cleanup,
+ .queue = nbd_queue,
+ .getevents = nbd_getevents,
+ .event = nbd_event,
+ .io_u_init = nbd_io_u_init,
+ .io_u_free = nbd_io_u_free,
+
+ .open_file = nbd_open_file,
+ .invalidate = nbd_invalidate,
+};
+
+static void fio_init fio_nbd_register(void)
+{
+ register_ioengine(&ioengine);
+}
+
+static void fio_exit fio_nbd_unregister(void)
+{
+ unregister_ioengine(&ioengine);
+}
diff --git a/examples/nbd.fio b/examples/nbd.fio
new file mode 100644
index 00000000..27e15086
--- /dev/null
+++ b/examples/nbd.fio
@@ -0,0 +1,35 @@
+# To use fio to test nbdkit:
+#
+# nbdkit -U - memory size=256M --run 'export unixsocket; fio examples/nbd.fio'
+#
+# To use fio to test qemu-nbd:
+#
+# rm -f /tmp/disk.img /tmp/socket
+# truncate -s 256M /tmp/disk.img
+# export unixsocket=/tmp/socket
+# qemu-nbd -t -k $unixsocket -f raw /tmp/disk.img &
+# fio examples/nbd.fio
+# killall qemu-nbd
+
+[global]
+ioengine=nbd
+uri=nbd+unix:///?socket=${unixsocket}
+# Starting from nbdkit 1.14 the following will work:
+#uri=${uri}
+rw=randrw
+time_based
+runtime=60
+group_reporting
+iodepth=64
+
+[job0]
+offset=0
+
+[job1]
+offset=064m
+
+[job2]
+offset=128m
+
+[job3]
+offset=192m
diff --git a/fio.1 b/fio.1
index 2966d9d5..30b17f02 100644
--- a/fio.1
+++ b/fio.1
@@ -1756,6 +1756,9 @@ FIO will then decide when to commit these requests.
.TP
.B libiscsi
Read and write iscsi lun with libiscsi.
+.TP
+.B nbd
+Synchronous read and write a Network Block Device (NBD).
.SS "I/O engine specific parameters"
In addition, there are some parameters which are only valid when a specific
\fBioengine\fR is in use. These are used identically to normal parameters,
diff --git a/optgroup.c b/optgroup.c
index 04ceec7e..c228ff29 100644
--- a/optgroup.c
+++ b/optgroup.c
@@ -169,6 +169,10 @@ static const struct opt_group fio_opt_cat_groups[] = {
.name = "libhdfs I/O engine", /* libhdfs */
.mask = FIO_OPT_G_HDFS,
},
+ {
+ .name = "NBD I/O engine", /* NBD */
+ .mask = FIO_OPT_G_NBD,
+ },
{
.name = NULL,
},
diff --git a/optgroup.h b/optgroup.h
index 148c8da1..8009bf25 100644
--- a/optgroup.h
+++ b/optgroup.h
@@ -63,6 +63,7 @@ enum opt_category_group {
__FIO_OPT_G_SG,
__FIO_OPT_G_MMAP,
__FIO_OPT_G_ISCSI,
+ __FIO_OPT_G_NBD,
__FIO_OPT_G_NR,
FIO_OPT_G_RATE = (1ULL << __FIO_OPT_G_RATE),
@@ -102,6 +103,7 @@ enum opt_category_group {
FIO_OPT_G_MMAP = (1ULL << __FIO_OPT_G_MMAP),
FIO_OPT_G_INVALID = (1ULL << __FIO_OPT_G_NR),
FIO_OPT_G_ISCSI = (1ULL << __FIO_OPT_G_ISCSI),
+ FIO_OPT_G_NBD = (1ULL << __FIO_OPT_G_NBD),
};
extern const struct opt_group *opt_group_from_mask(uint64_t *mask);
diff --git a/options.c b/options.c
index 95086074..f4c9bedf 100644
--- a/options.c
+++ b/options.c
@@ -1899,6 +1899,9 @@ struct fio_option fio_options[FIO_MAX_OPTS] = {
.help = "HTTP (WebDAV/S3) IO engine",
},
#endif
+ { .ival = "nbd",
+ .help = "Network Block Device (NBD) IO engine"
+ },
},
},
{
--
2.22.0
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH v4] engines: Add Network Block Device (NBD) support using libnbd.
2019-08-02 15:32 ` Richard W.M. Jones
@ 2019-08-02 15:40 ` Jens Axboe
2019-08-03 15:10 ` Sitsofe Wheeler
1 sibling, 0 replies; 5+ messages in thread
From: Jens Axboe @ 2019-08-02 15:40 UTC (permalink / raw)
To: Richard W.M. Jones, fio; +Cc: eblake
On 8/2/19 9:32 AM, Richard W.M. Jones wrote:
> diff --git a/engines/nbd.c b/engines/nbd.c
> new file mode 100644
> index 00000000..399da5f3
> --- /dev/null
> +++ b/engines/nbd.c
> @@ -0,0 +1,368 @@
> +/*
> + * NBD engine
> + *
> + * IO engine that talks to an NBD server.
> + *
> + * Copyright (C) 2019 Red Hat Inc.
> + * Written by Richard W.M. Jones <rjones@redhat.com>
> + *
> + */
> +
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <stdint.h>
> +#include <errno.h>
> +
> +#include <libnbd.h>
> +
> +#include "../fio.h"
> +#include "../optgroup.h"
> +
> +/* Actually this differs across servers, but for nbdkit ... */
> +#define NBD_MAX_REQUEST_SIZE (64 * 1024 * 1024)
> +
> +/* Storage for the NBD handle. */
> +struct nbd_data {
> + struct nbd_handle *nbd;
> + int debug;
Here (and lots of other places) you have a mix of tabs and spaces.
Please make them all tab based.
--
Jens Axboe
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v4] engines: Add Network Block Device (NBD) support using libnbd.
2019-08-02 15:32 ` Richard W.M. Jones
2019-08-02 15:40 ` Jens Axboe
@ 2019-08-03 15:10 ` Sitsofe Wheeler
2019-08-03 15:32 ` Richard W.M. Jones
1 sibling, 1 reply; 5+ messages in thread
From: Sitsofe Wheeler @ 2019-08-03 15:10 UTC (permalink / raw)
To: Richard W.M. Jones; +Cc: fio, eblake, Jens Axboe
On Sat, 3 Aug 2019 at 15:38, Richard W.M. Jones <rjones@redhat.com> wrote:
>
> This commit adds a new engine for testing Network Block Devices
> directly. It requires libnbd (https://github.com/libguestfs/libnbd).
>
> To see how to test nbdkit or qemu-nbd read examples/nbd.fio.
>
> Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
> ---
> HOWTO | 2 +
> Makefile | 6 +
> configure | 27 ++++
> engines/nbd.c | 368 +++++++++++++++++++++++++++++++++++++++++++++++
> examples/nbd.fio | 35 +++++
> fio.1 | 3 +
> optgroup.c | 4 +
> optgroup.h | 2 +
> options.c | 3 +
> 9 files changed, 450 insertions(+)
>
> diff --git a/HOWTO b/HOWTO
> index 81244064..955ea43c 100644
> --- a/HOWTO
> +++ b/HOWTO
> @@ -1998,6 +1998,8 @@ I/O engine
> requests for IME. FIO will then decide when to commit these requests.
> **libiscsi**
> Read and write iscsi lun with libiscsi.
> + **nbd**
> + Synchronous read and write a Network Block Device (NBD).
I wonder if the engine should be called nbdkit as that's what it uses
under hood to talk NBD...
>
> I/O engine specific parameters
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> diff --git a/Makefile b/Makefile
> index d7e5fca7..fe02bf1d 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -65,6 +65,12 @@ ifdef CONFIG_LIBISCSI
> SOURCE += engines/libiscsi.c
> endif
>
> +ifdef CONFIG_LIBNBD
> + CFLAGS += $(LIBNBD_CFLAGS)
> + LIBS += $(LIBNBD_LIBS)
> + SOURCE += engines/nbd.c
> +endif
> +
> ifdef CONFIG_64BIT
> CFLAGS += -DBITS_PER_LONG=64
> endif
> diff --git a/configure b/configure
> index a0692d58..b11b2dce 100755
> --- a/configure
> +++ b/configure
> @@ -149,6 +149,7 @@ disable_pmem="no"
> disable_native="no"
> march_set="no"
> libiscsi="no"
> +libnbd="no"
> prefix=/usr/local
>
> # parse options
> @@ -207,6 +208,8 @@ for opt do
> ;;
> --enable-libiscsi) libiscsi="yes"
> ;;
> + --enable-libnbd) libnbd="yes"
> + ;;
Why not enable by default if available and then do a probe to see if
it can be enabled?
> +
> +static struct ioengine_ops ioengine = {
> + .name = "nbd",
> + .version = FIO_IOOPS_VERSION,
> + .options = options,
> + .option_struct_size = sizeof(struct nbd_options),
> + .flags = FIO_DISKLESSIO | FIO_NOEXTEND,
> +
> + .setup = nbd_setup,
> + .init = nbd_init,
> + .cleanup = nbd_cleanup,
> + .queue = nbd_queue,
> + .getevents = nbd_getevents,
> + .event = nbd_event,
> + .io_u_init = nbd_io_u_init,
> + .io_u_free = nbd_io_u_free,
> +
> + .open_file = nbd_open_file,
> + .invalidate = nbd_invalidate,
Do you have to register functions for things that you don't do
anything (e.g. nbd_io_u_free)?
> --- /dev/null
> +++ b/examples/nbd.fio
> @@ -0,0 +1,35 @@
> +# To use fio to test nbdkit:
> +#
> +# nbdkit -U - memory size=256M --run 'export unixsocket; fio examples/nbd.fio'
> +#
> +# To use fio to test qemu-nbd:
> +#
> +# rm -f /tmp/disk.img /tmp/socket
> +# truncate -s 256M /tmp/disk.img
> +# export unixsocket=/tmp/socket
> +# qemu-nbd -t -k $unixsocket -f raw /tmp/disk.img &
> +# fio examples/nbd.fio
> +# killall qemu-nbd
> +
> +[global]
> +ioengine=nbd
> +uri=nbd+unix:///?socket=${unixsocket}
> +# Starting from nbdkit 1.14 the following will work:
> +#uri=${uri}
> +rw=randrw
> +time_based
> +runtime=60
> +group_reporting
> +iodepth=64
> +
> +[job0]
> +offset=0
> +
> +[job1]
> +offset=064m
I'd drop the leading 0.
--
Sitsofe | http://sucs.org/~sits/
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v4] engines: Add Network Block Device (NBD) support using libnbd.
2019-08-03 15:10 ` Sitsofe Wheeler
@ 2019-08-03 15:32 ` Richard W.M. Jones
0 siblings, 0 replies; 5+ messages in thread
From: Richard W.M. Jones @ 2019-08-03 15:32 UTC (permalink / raw)
To: Sitsofe Wheeler; +Cc: fio, eblake, Jens Axboe
On Sat, Aug 03, 2019 at 04:10:07PM +0100, Sitsofe Wheeler wrote:
> On Sat, 3 Aug 2019 at 15:38, Richard W.M. Jones <rjones@redhat.com> wrote:
> > + **nbd**
> > + Synchronous read and write a Network Block Device (NBD).
>
> I wonder if the engine should be called nbdkit as that's what it uses
> under hood to talk NBD...
libnbd (nbdkit is a server). libnbd is supposed to be "the" NBD
client library however. I'm not sure what other NBD engines would be
useful here.
> > + --enable-libnbd) libnbd="yes"
> > + ;;
>
> Why not enable by default if available and then do a probe to see if
> it can be enabled?
Yes, we can do this. I disabled it out of an abundance of caution, so
that no one's build could be broken if I got it wrong.
> > + .io_u_free = nbd_io_u_free,
> > +
> > + .open_file = nbd_open_file,
> > + .invalidate = nbd_invalidate,
>
> Do you have to register functions for things that you don't do
> anything (e.g. nbd_io_u_free)?
I think io_u_free is the only one which is an actual no-op (but it
balances the corresponding init function). I'm not really sure of the
purpose of open_file and invalidate except that other engines also did
the same thing.
> > +offset=064m
>
> I'd drop the leading 0.
This is a bug, I'll send a follow-up patch to fix it.
Rich.
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
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^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2019-08-03 15:32 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
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2019-08-02 15:32 [PATCH v4] engines: Add Network Block Device (NBD) support using libnbd Richard W.M. Jones
2019-08-02 15:32 ` Richard W.M. Jones
2019-08-02 15:40 ` Jens Axboe
2019-08-03 15:10 ` Sitsofe Wheeler
2019-08-03 15:32 ` Richard W.M. Jones
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