Offset modifiers such as rw=readwrite:8 or rw=write:4K can create
overlaps. For these cases use RB tree instead of list to log the I/O
entries.
Add a helper function fio_offset_overlap_risk() to decide whether to log
the I/O entry in an RB tree or a list.
Disable header seed verification if there are offset modifiers, unless
its explicitly enabled.
fixes #1503
Signed-off-by: Ankit Kumar <ankit.kumar@xxxxxxxxxxx>
---
HOWTO.rst | 4 +++-
fio.1 | 4 +++-
fio.h | 8 ++++++++
init.c | 6 ++++--
iolog.c | 9 +++++----
5 files changed, 23 insertions(+), 8 deletions(-)
diff --git a/HOWTO.rst b/HOWTO.rst
index 4293c03c..bb5da1cc 100644
--- a/HOWTO.rst
+++ b/HOWTO.rst
@@ -1185,7 +1185,9 @@ I/O type
pattern, then the *<nr>* value specified will be **added** to the generated
offset for each I/O turning sequential I/O into sequential I/O with holes.
For instance, using ``rw=write:4k`` will skip 4k for every write. Also see
- the :option:`rw_sequencer` option.
+ the :option:`rw_sequencer` option. If this is used with :option:`verify`
+ then :option:`verify_header_seed` will be disabled, unless its explicitly
+ enabled.
.. option:: rw_sequencer=str
diff --git a/fio.1 b/fio.1
index a0f204c0..4755ca19 100644
--- a/fio.1
+++ b/fio.1
@@ -955,7 +955,9 @@ modifier with a value of 8. If the suffix is used with a sequential I/O
pattern, then the `<nr>' value specified will be added to the generated
offset for each I/O turning sequential I/O into sequential I/O with holes.
For instance, using `rw=write:4k' will skip 4k for every write. Also see
-the \fBrw_sequencer\fR option.
+the \fBrw_sequencer\fR option. If this is used with \fBverify\fR then
+\fBverify_header_seed\fR option will be disabled, unless its explicitly
+enabled.
.RE
.TP
.BI rw_sequencer \fR=\fPstr
diff --git a/fio.h b/fio.h
index b8cf3229..c7c0d147 100644
--- a/fio.h
+++ b/fio.h
@@ -800,6 +800,14 @@ extern void lat_target_reset(struct thread_data *);
(i) < (td)->o.nr_files && ((f) = (td)->files[i]) != NULL; \
(i)++)
+static inline bool fio_offset_overlap_risk(struct thread_data *td)
+{
+ if (td->o.ddir_seq_add || (td->o.ddir_seq_nr > 1))
+ return true;
+
+ return false;
+}
+
static inline bool fio_fill_issue_time(struct thread_data *td)
{
if (td->o.read_iolog_file ||
diff --git a/init.c b/init.c
index bf257ea1..feaa3f28 100644
--- a/init.c
+++ b/init.c
@@ -886,11 +886,13 @@ static int fixup_options(struct thread_data *td)
/*
* Disable rand_seed check when we have verify_backlog,
- * zone reset frequency for zonemode=zbd, or norandommap.
+ * zone reset frequency for zonemode=zbd, norandommap, or
+ * offset modifiers.
* Unless we were explicitly asked to enable it.
*/
if (!td_write(td) || (td->flags & TD_F_VER_BACKLOG) ||
- o->zrf.u.f || o->norandommap) {
+ o->zrf.u.f || o->norandommap ||
+ fio_offset_overlap_risk(td)) {
if (!fio_option_is_set(o, verify_header_seed))
o->verify_header_seed = 0;
}
diff --git a/iolog.c b/iolog.c
index ef173b09..6b5dc9ab 100644
--- a/iolog.c
+++ b/iolog.c
@@ -301,11 +301,12 @@ void log_io_piece(struct thread_data *td, struct io_u *io_u)
}
/*
- * Only sort writes if we don't have a random map in which case we need
- * to check for duplicate blocks and drop the old one, which we rely on
- * the rb insert/lookup for handling.
+ * Sort writes if we don't have a random map in which case we need to
+ * check for duplicate blocks and drop the old one, which we rely on
+ * the rb insert/lookup for handling. Sort writes if we have offset
+ * modifier which can also create duplicate blocks.
*/
- if (file_randommap(td, ipo->file)) {
+ if (file_randommap(td, ipo->file) && !fio_offset_overlap_risk(td)) {
INIT_FLIST_HEAD(&ipo->list);
flist_add_tail(&ipo->list, &td->io_hist_list);
ipo->flags |= IP_F_ONLIST;
--
2.25.1
