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diff --git a/HOWTO b/HOWTO
index 60eab243..d62d4089 100644
--- a/HOWTO
+++ b/HOWTO
@@ -435,6 +435,7 @@ unified_rw_reporting=bool	Fio normally reports statistics on a per
 
 randrepeat=bool	For random IO workloads, seed the generator in a predictable
 		way so that results are repeatable across repetitions.
+		Defaults to true.
 
 randseed=int	Seed the random number generators based on this seed value, to
 		be able to control what sequence of output is being generated.
@@ -820,6 +821,18 @@ iodepth_low=int	The low water mark indicating when to start filling
 		after fio has filled the queue of 16 requests, it will let
 		the depth drain down to 4 before starting to fill it again.
 
+io_submit_mode=str	This option controls how fio submits the IO to
+		the IO engine. The default is 'inline', which means that the
+		fio job threads submit and reap IO directly. If set to
+		'offload', the job threads will offload IO submission to a
+		dedicated pool of IO threads. This requires some coordination
+		and thus has a bit of extra overhead, especially for lower
+		queue depth IO where it can increase latencies. The benefit
+		is that fio can manage submission rates independently of
+		the device completion rates. This avoids skewed latency
+		reporting if IO gets back up on the device side (the
+		coordinated omission problem).
+
 direct=bool	If value is true, use non-buffered io. This is usually
 		O_DIRECT. Note that ZFS on Solaris doesn't support direct io.
 		On Windows the synchronous ioengines don't support direct io.
@@ -1421,6 +1434,12 @@ 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_align=int	Force alignment of IO offsets and lengths in a trace
+		to this power of 2 value.
+
+replay_scale=int	Scale sector offsets down by this factor when
+		replaying traces.
+
 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
@@ -1998,6 +2017,7 @@ before it can be used with this format. The offset and length are given in
 bytes. The action can be one of these:
 
 wait       Wait for 'offset' microseconds. Everything below 100 is discarded.
+	   The time is relative to the previous wait statement.
 read       Read 'length' bytes beginning from 'offset'
 write      Write 'length' bytes beginning from 'offset'
 sync       fsync() the file