From: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx>
Introduce the new option cmdprio_hint to allow specifying I/O priority
hints per IO with the iouring and libaio IO engines. A third acceptable
format for the cmdprio_bssplit option is also introduced to allow
specifying an IO hint in addition to a priority class and level.
Signed-off-by: Damien Le Moal <damien.lemoal@xxxxxxxxxxxxxxxxxx>
---
HOWTO.rst | 25 +++++++++++++++++++++----
engines/cmdprio.c | 9 ++++++---
engines/cmdprio.h | 1 +
engines/io_uring.c | 25 +++++++++++++++++++++++--
engines/libaio.c | 21 +++++++++++++++++++++
fio.1 | 24 +++++++++++++++++++++---
options.c | 13 ++++++++++---
7 files changed, 103 insertions(+), 15 deletions(-)
diff --git a/HOWTO.rst b/HOWTO.rst
index 359d606b..16985269 100644
--- a/HOWTO.rst
+++ b/HOWTO.rst
@@ -2275,6 +2275,16 @@ with the caveat that when used on the command line, they must come after the
reads and writes. See :manpage:`ionice(1)`. See also the
:option:`prioclass` option.
+.. option:: cmdprio_hint=int[,int] : [io_uring] [libaio]
+
+ Set the I/O priority hint to use for I/Os that must be issued with
+ a priority when :option:`cmdprio_percentage` or
+ :option:`cmdprio_bssplit` is set. If not specified when
+ :option:`cmdprio_percentage` or :option:`cmdprio_bssplit` is set,
+ this defaults to 0 (no hint). A single value applies to reads and
+ writes. Comma-separated values may be specified for reads and writes.
+ See also the :option:`priohint` option.
+
.. option:: cmdprio=int[,int] : [io_uring] [libaio]
Set the I/O priority value to use for I/Os that must be issued with
@@ -2301,9 +2311,9 @@ with the caveat that when used on the command line, they must come after the
cmdprio_bssplit=blocksize/percentage:blocksize/percentage
- In this case, each entry will use the priority class and priority
- level defined by the options :option:`cmdprio_class` and
- :option:`cmdprio` respectively.
+ In this case, each entry will use the priority class, priority hint
+ and priority level defined by the options :option:`cmdprio_class`,
+ :option:`cmdprio` and :option:`cmdprio_hint` respectively.
The second accepted format for this option is:
@@ -2314,7 +2324,14 @@ with the caveat that when used on the command line, they must come after the
accepted format does not restrict all entries to have the same priority
class and priority level.
- For both formats, only the read and write data directions are supported,
+ The third accepted format for this option is:
+
+ cmdprio_bssplit=blocksize/percentage/class/level/hint:...
+
+ This is an extension of the second accepted format that allows to also
+ specify a priority hint.
+
+ For all formats, only the read and write data directions are supported,
values for trim IOs are ignored. This option is mutually exclusive with
the :option:`cmdprio_percentage` option.
diff --git a/engines/cmdprio.c b/engines/cmdprio.c
index e6ff1fc2..153e3691 100644
--- a/engines/cmdprio.c
+++ b/engines/cmdprio.c
@@ -267,7 +267,8 @@ static int fio_cmdprio_percentage(struct cmdprio *cmdprio, struct io_u *io_u,
* to be set. If the random percentage value is within the user specified
* percentage of I/Os that should use a cmdprio priority value (rather than
* the default priority), then this function updates the io_u with an ioprio
- * value as defined by the cmdprio/cmdprio_class or cmdprio_bssplit options.
+ * value as defined by the cmdprio/cmdprio_hint/cmdprio_class or
+ * cmdprio_bssplit options.
*
* Return true if the io_u ioprio was changed and false otherwise.
*/
@@ -342,7 +343,8 @@ static int fio_cmdprio_gen_perc(struct thread_data *td, struct cmdprio *cmdprio)
prio = &cmdprio->perc_entry[ddir];
prio->perc = options->percentage[ddir];
prio->prio = ioprio_value(options->class[ddir],
- options->level[ddir], 0);
+ options->level[ddir],
+ options->hint[ddir]);
assign_clat_prio_index(prio, &values[ddir]);
ret = init_ts_clat_prio(ts, ddir, &values[ddir]);
@@ -400,7 +402,8 @@ static int fio_cmdprio_parse_and_gen_bssplit(struct thread_data *td,
goto err;
implicit_cmdprio = ioprio_value(options->class[ddir],
- options->level[ddir], 0);
+ options->level[ddir],
+ options->hint[ddir]);
ret = fio_cmdprio_generate_bsprio_desc(&cmdprio->bsprio_desc[ddir],
&parse_res[ddir],
diff --git a/engines/cmdprio.h b/engines/cmdprio.h
index 755da8d0..9b351828 100644
--- a/engines/cmdprio.h
+++ b/engines/cmdprio.h
@@ -39,6 +39,7 @@ struct cmdprio_options {
unsigned int percentage[CMDPRIO_RWDIR_CNT];
unsigned int class[CMDPRIO_RWDIR_CNT];
unsigned int level[CMDPRIO_RWDIR_CNT];
+ unsigned int hint[CMDPRIO_RWDIR_CNT];
char *bssplit_str;
};
diff --git a/engines/io_uring.c b/engines/io_uring.c
index 5021239e..975a0a4d 100644
--- a/engines/io_uring.c
+++ b/engines/io_uring.c
@@ -157,6 +157,21 @@ static struct fio_option options[] = {
.category = FIO_OPT_C_ENGINE,
.group = FIO_OPT_G_IOURING,
},
+ {
+ .name = "cmdprio_hint",
+ .lname = "Asynchronous I/O priority hint",
+ .type = FIO_OPT_INT,
+ .off1 = offsetof(struct ioring_options,
+ cmdprio_options.hint[DDIR_READ]),
+ .off2 = offsetof(struct ioring_options,
+ cmdprio_options.hint[DDIR_WRITE]),
+ .help = "Set asynchronous IO priority hint",
+ .minval = IOPRIO_MIN_PRIO_HINT,
+ .maxval = IOPRIO_MAX_PRIO_HINT,
+ .interval = 1,
+ .category = FIO_OPT_C_ENGINE,
+ .group = FIO_OPT_G_IOURING,
+ },
{
.name = "cmdprio",
.lname = "Asynchronous I/O priority level",
@@ -195,6 +210,12 @@ static struct fio_option options[] = {
.type = FIO_OPT_UNSUPPORTED,
.help = "Your platform does not support I/O priority classes",
},
+ {
+ .name = "cmdprio_hint",
+ .lname = "Asynchronous I/O priority hint",
+ .type = FIO_OPT_UNSUPPORTED,
+ .help = "Your platform does not support I/O priority classes",
+ },
{
.name = "cmdprio",
.lname = "Asynchronous I/O priority level",
@@ -365,8 +386,8 @@ static int fio_ioring_prep(struct thread_data *td, struct io_u *io_u)
/*
* Since io_uring can have a submission context (sqthread_poll)
* that is different from the process context, we cannot rely on
- * the IO priority set by ioprio_set() (option prio/prioclass)
- * to be inherited.
+ * the IO priority set by ioprio_set() (options prio, prioclass,
+ * and priohint) to be inherited.
* td->ioprio will have the value of the "default prio", so set
* this unconditionally. This value might get overridden by
* fio_ioring_cmdprio_prep() if the option cmdprio_percentage or
diff --git a/engines/libaio.c b/engines/libaio.c
index 6a0745aa..c52d05fe 100644
--- a/engines/libaio.c
+++ b/engines/libaio.c
@@ -102,6 +102,21 @@ static struct fio_option options[] = {
.category = FIO_OPT_C_ENGINE,
.group = FIO_OPT_G_LIBAIO,
},
+ {
+ .name = "cmdprio_hint",
+ .lname = "Asynchronous I/O priority hint",
+ .type = FIO_OPT_INT,
+ .off1 = offsetof(struct libaio_options,
+ cmdprio_options.hint[DDIR_READ]),
+ .off2 = offsetof(struct libaio_options,
+ cmdprio_options.hint[DDIR_WRITE]),
+ .help = "Set asynchronous IO priority hint",
+ .minval = IOPRIO_MIN_PRIO_HINT,
+ .maxval = IOPRIO_MAX_PRIO_HINT,
+ .interval = 1,
+ .category = FIO_OPT_C_ENGINE,
+ .group = FIO_OPT_G_LIBAIO,
+ },
{
.name = "cmdprio",
.lname = "Asynchronous I/O priority level",
@@ -140,6 +155,12 @@ static struct fio_option options[] = {
.type = FIO_OPT_UNSUPPORTED,
.help = "Your platform does not support I/O priority classes",
},
+ {
+ .name = "cmdprio_hint",
+ .lname = "Asynchronous I/O priority hint",
+ .type = FIO_OPT_UNSUPPORTED,
+ .help = "Your platform does not support I/O priority classes",
+ },
{
.name = "cmdprio",
.lname = "Asynchronous I/O priority level",
diff --git a/fio.1 b/fio.1
index 6dbdb293..72afff65 100644
--- a/fio.1
+++ b/fio.1
@@ -2072,6 +2072,14 @@ is set, this defaults to the highest priority class. A single value applies
to reads and writes. Comma-separated values may be specified for reads and
writes. See man \fBionice\fR\|(1). See also the \fBprioclass\fR option.
.TP
+.BI (io_uring,libaio)cmdprio_hint \fR=\fPint[,int]
+Set the I/O priority hint to use for I/Os that must be issued with a
+priority when \fBcmdprio_percentage\fR or \fBcmdprio_bssplit\fR is set.
+If not specified when \fBcmdprio_percentage\fR or \fBcmdprio_bssplit\fR
+is set, this defaults to 0 (no hint). A single value applies to reads and
+writes. Comma-separated values may be specified for reads and writes.
+See also the \fBpriohint\fR option.
+.TP
.BI (io_uring,libaio)cmdprio \fR=\fPint[,int]
Set the I/O priority value to use for I/Os that must be issued with a
priority when \fBcmdprio_percentage\fR or \fBcmdprio_bssplit\fR is set.
@@ -2097,8 +2105,9 @@ The first accepted format for this option is the same as the format of the
cmdprio_bssplit=blocksize/percentage:blocksize/percentage
.RE
.P
-In this case, each entry will use the priority class and priority level defined
-by the options \fBcmdprio_class\fR and \fBcmdprio\fR respectively.
+In this case, each entry will use the priority class, priority hint and
+priority level defined by the options \fBcmdprio_class\fR, \fBcmdprio\fR
+and \fBcmdprio_hint\fR respectively.
.P
The second accepted format for this option is:
.RS
@@ -2111,7 +2120,16 @@ entry. In comparison with the first accepted format, the second accepted format
does not restrict all entries to have the same priority class and priority
level.
.P
-For both formats, only the read and write data directions are supported, values
+The third accepted format for this option is:
+.RS
+.P
+cmdprio_bssplit=blocksize/percentage/class/level/hint:...
+.RE
+.P
+This is an extension of the second accepted format that allows to also
+specify a priority hint.
+.P
+For all formats, only the read and write data directions are supported, values
for trim IOs are ignored. This option is mutually exclusive with the
\fBcmdprio_percentage\fR option.
.RE
diff --git a/options.c b/options.c
index c1246297..3fcbd2b3 100644
--- a/options.c
+++ b/options.c
@@ -313,15 +313,17 @@ static int parse_cmdprio_bssplit_entry(struct thread_options *o,
int matches = 0;
char *bs_str = NULL;
long long bs_val;
- unsigned int perc = 0, class, level;
+ unsigned int perc = 0, class, level, hint;
/*
* valid entry formats:
* bs/ - %s/ - set perc to 0, prio to -1.
* bs/perc - %s/%u - set prio to -1.
* bs/perc/class/level - %s/%u/%u/%u
+ * bs/perc/class/level/hint - %s/%u/%u/%u/%u
*/
- matches = sscanf(str, "%m[^/]/%u/%u/%u", &bs_str, &perc, &class, &level);
+ matches = sscanf(str, "%m[^/]/%u/%u/%u/%u",
+ &bs_str, &perc, &class, &level, &hint);
if (matches < 1) {
log_err("fio: invalid cmdprio_bssplit format\n");
return 1;
@@ -342,9 +344,14 @@ static int parse_cmdprio_bssplit_entry(struct thread_options *o,
case 2: /* bs/perc case */
break;
case 4: /* bs/perc/class/level case */
+ case 5: /* bs/perc/class/level/hint case */
class = min(class, (unsigned int) IOPRIO_MAX_PRIO_CLASS);
level = min(level, (unsigned int) IOPRIO_MAX_PRIO);
- entry->prio = ioprio_value(class, level, 0);
+ if (matches == 5)
+ hint = min(hint, (unsigned int) IOPRIO_MAX_PRIO_HINT);
+ else
+ hint = 0;
+ entry->prio = ioprio_value(class, level, hint);
break;
default:
log_err("fio: invalid cmdprio_bssplit format\n");
--
2.41.0
