\fBserialize_overlap\fR tells fio to avoid provoking this behavior by explicitly
serializing in-flight I/Os that have a non-zero overlap. Note that setting
this option can reduce both performance and the \fBiodepth\fR achieved.
-Additionally this option does not work when \fBio_submit_mode\fR is set to
-offload. Default: false.
+.RS
+.P
+This option only applies to I/Os issued for a single job except when it is
+enabled along with \fBio_submit_mode\fR=offload. In offload mode, fio
+will check for overlap among all I/Os submitted by offload jobs with \fBserialize_overlap\fR
+enabled. Threads must be used for all such jobs.
+.P
+Default: false.
+.RE
.TP
.BI io_submit_mode \fR=\fPstr
This option controls how fio submits the I/O to the I/O engine. The default
device accesses.
.TP
.BI replay_align \fR=\fPint
-Force alignment of I/O offsets and lengths in a trace to this power of 2
-value.
+Force alignment of the byte offsets in a trace to this value. The value
+must be a power of 2.
.TP
.BI replay_scale \fR=\fPint
-Scale sector offsets down by this factor when replaying traces.
+Scale bye offsets down by this factor when replaying traces. Should most
+likely use \fBreplay_align\fR as well.
.SS "Threads, processes and job synchronization"
.TP
.BI replay_skip \fR=\fPstr