> But since I also wanted to have each thread accessing different
> parts of the disk to increase a load, but still following the
> access pattern of the original, I added "replay_rebase" option to
> shift offset of IO request for each thread.
>
>> Thanks, I can see this being handy. I can apply this, but I would
>> much prefer if you resend it with the proper updates to HOWTO and
>> fio.1 adding the new option. Otherwise nobody is going to learn about it.
Yes, you're right.
Here's an updated patch with documentation.
Best Regards,
Signed-off-by: Taisuke Yamada <tai@xxxxxxxxxxxx>
---
HOWTO | 9 +++++++++
fio.1 | 9 +++++++++
fio.h | 1 +
log.c | 2 +-
options.c | 8 ++++++++
5 files changed, 28 insertions(+), 1 deletions(-)
diff --git a/HOWTO b/HOWTO
index 724b604..132dc4a 100644
--- a/HOWTO
+++ b/HOWTO
@@ -1078,6 +1078,15 @@ replay_redirect=str While replaying I/O patterns using read_iolog the
independent fio invocations. Unfortuantely this also breaks
the strict time ordering between multiple device accesses.
+replay_rebase=int While replaying I/O patterns using read_iolog, the
+ default behavior is to replay the log as-is, even when
+ multiple threads are replaying the same log. This means
+ all threads are accessing the same sector on the device.
+ By specifying this option, each thread will be accessing
+ different sector by adding extra rebase offset. Offset is
+ simply given by "replay_rebase * internal thread number",
+ so IO access pattern itself is preserved.
+
write_bw_log=str If given, write a bandwidth log of the jobs in this job
file. Can be used to store data of the bandwidth of the
jobs in their lifetime. The included fio_generate_plots
diff --git a/fio.1 b/fio.1
index ffc97c9..702e4e3 100644
--- a/fio.1
+++ b/fio.1
@@ -823,6 +823,15 @@ is to replay the IOPS onto the major/minor device that each IOP was recorded
from. Setting \fBreplay_redirect\fR causes all IOPS to be replayed onto the
single specified device regardless of the device it was recorded from.
.TP
+.BI replay_rebase \fR=\fPint
+While replaying I/O patterns using read_iolog, the default behavior
+is to replay the log as-is, even when multiple threads are replaying
+the same log. This means all threads are accessing the same sector
+on the device. By specifying this option, each thread will be accessing
+different sector by adding extra rebase offset. Offset is simply given
+by "replay_rebase * internal thread number", so IO access pattern itself
+is preserved.
+.TP
.B write_bw_log \fR=\fPstr
If given, write a bandwidth log of the jobs in this job file. Can be used to
store data of the bandwidth of the jobs in their lifetime. The included
diff --git a/fio.h b/fio.h
index 6eb270d..b28e0ae 100644
--- a/fio.h
+++ b/fio.h
@@ -358,6 +358,7 @@ struct thread_options {
unsigned int gtod_offload;
enum fio_cs clocksource;
unsigned int no_stall;
+ unsigned int replay_rebase;
unsigned int trim_percentage;
unsigned int trim_batch;
unsigned int trim_zero;
diff --git a/log.c b/log.c
index f962864..57fc0f4 100644
--- a/log.c
+++ b/log.c
@@ -129,7 +129,7 @@ int read_iolog_get(struct thread_data *td, struct io_u *io_u)
io_u->ddir = ipo->ddir;
if (ipo->ddir != DDIR_WAIT) {
- io_u->offset = ipo->offset;
+ io_u->offset = ipo->offset + td->o.replay_rebase * td->thread_number;
io_u->buflen = ipo->len;
io_u->file = td->files[ipo->fileno];
get_file(io_u->file);
diff --git a/options.c b/options.c
index 74c24d0..aba14b1 100644
--- a/options.c
+++ b/options.c
@@ -1654,6 +1654,14 @@ static struct fio_option options[FIO_MAX_OPTS] = {
.help = "Replay all I/O onto this device, regardless of trace device",
},
{
+ .name = "replay_rebase",
+ .type = FIO_OPT_INT,
+ .off1 = td_var_offset(replay_rebase),
+ .def = "0",
+ .parent = "read_iolog",
+ .help = "Apply given offset for IO replay. Mainly for parallel replay.",
+ },
+ {
.name = "exec_prerun",
.type = FIO_OPT_STR_STORE,
.off1 = td_var_offset(exec_prerun),
