X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;f=HOWTO;h=d8c6b9414eef85be48779d7018682cf2bbd07470;hb=c0a5d35ec77fae5cfe382d35ab18915ed6766504;hp=7b717f7739664f44393d67b7b6521e8ca0404eae;hpb=aa31f1f108348ba2a8749c73fa8c25f3d4630a7c;p=fio.git

diff --git a/HOWTO b/HOWTO
index 7b717f77..d8c6b941 100644
--- a/HOWTO
+++ b/HOWTO
@@ -344,6 +344,8 @@ ioengine=str	Defines how the job issues io to the file. The following
 
 			psync 	Basic pread(2) or pwrite(2) io.
 
+			vsync	Basic readv(2) or writev(2) IO.
+
 			libaio	Linux native asynchronous io.
 
 			posixaio glibc posix asynchronous io.
@@ -381,7 +383,10 @@ ioengine=str	Defines how the job issues io to the file. The following
 				cycles according to the cpuload= and
 				cpucycle= options. Setting cpuload=85
 				will cause that job to do nothing but burn
-				85% of the CPU.
+				85% of the CPU. In case of SMP machines,
+				use numjobs=<no_of_cpu> to get desired CPU
+				usage, as the cpuload only loads a single
+				CPU at the desired rate.
 
 			guasi	The GUASI IO engine is the Generic Userspace
 				Asyncronous Syscall Interface approach
@@ -402,8 +407,9 @@ iodepth=int	This defines how many io units to keep in flight against
 		concurrency.
 
 iodepth_batch=int This defines how many pieces of IO to submit at once.
-		It defaults to the same as iodepth, but can be set lower
-		if one so desires.
+		It defaults to 1 which means that we submit each IO
+		as soon as it is available, but can be raised to submit
+		bigger batches of IO at the time.
 
 iodepth_low=int	The low water mark indicating when to start filling
 		the queue again. Defaults to the same as iodepth, meaning
@@ -629,15 +635,6 @@ verify=str	If writing to a file, fio can verify the file contents
 				(timestamp, block number etc.). The block
 				number is verified.
 
-			pattern	Fill the IO buffers with a specific pattern,
-				that we can use to verify. Depending on the
-				width of the pattern, fio will fill 1/2/3/4
-				bytes of the buffer at the time. The pattern
-				cannot be larger than a 32-bit quantity. The
-				given pattern is given as a postfix to this
-				option, ala: verify=pattern:0x5a. It accepts
-				both hex and dec values.
-
 			null	Only pretend to verify. Useful for testing
 				internals with ioengine=null, not for much
 				else.
@@ -663,6 +660,14 @@ verify_interval=siint	Write the verification header at a finer granularity
 			size of header_interval. blocksize should divide this
 			evenly.
 
+verify_pattern=int	If set, fio will fill the io buffers with this
+		pattern. Fio defaults to filling with totally random
+		bytes, but sometimes it's interesting to fill with a known
+		pattern for io verification purposes. Depending on the
+		width of the pattern, fio will fill 1/2/3/4 bytes of the
+		buffer at the time. The verify_pattern cannot be larger than
+		a 32-bit quantity.
+
 verify_fatal=bool	Normally fio will keep checking the entire contents
 		before quitting on a block verification failure. If this
 		option is set, fio will exit the job on the first observed