X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;f=HOWTO;h=1b34c283af0f385e00407a9167c6ec02820ad4a1;hb=8aeebd5570ac4fccbcdd48f2e6f1cf1577f3c08d;hp=3b270b1d723460110607b1c2b455d61f35164d06;hpb=56bb17f297c50b2832c845b0f6cdde5063748b34;p=fio.git

diff --git a/HOWTO b/HOWTO
index 3b270b1d..1b34c283 100644
--- a/HOWTO
+++ b/HOWTO
@@ -319,7 +319,13 @@ prioclass=int	Set the io priority class. See man ionice(1).
 
 thinktime=int	Stall the job x microseconds after an io has completed before
 		issuing the next. May be used to simulate processing being
-		done by an application.
+		done by an application. See thinktime_blocks.
+
+thinktime_blocks
+		Only valid if thinktime is set - control how many blocks
+		to issue, before waiting 'thinktime' usecs. If not set,
+		defaults to 1 which will make fio wait 'thinktime' usecs
+		after every block.
 
 rate=int	Cap the bandwidth used by this job to this number of KiB/sec.
 
@@ -359,8 +365,10 @@ mem=str		Fio can use various types of memory as the io unit buffer.
 
 			shmhuge	Same as shm, but use huge pages as backing.
 
-			mmap	Use anonymous memory maps as the buffers.
-				Allocated through mmap(2).
+			mmap	Use mmap to allocate buffers. May either be
+				anonymous memory, or can be file backed if
+				a filename is given after the option. The
+				format is mem=mmap:/path/to/file.
 
 			mmaphuge Use a memory mapped huge file as the buffer
 				backing. Append filename after mmaphuge, ala
@@ -387,6 +395,9 @@ mem=str		Fio can use various types of memory as the io unit buffer.
 hugepage-size=siint
 		Defines the size of a huge page. Must at least be equal
 		to the system setting, see /proc/meminfo. Defaults to 4MiB.
+		Should probably always be a multiple of megabytes, so using
+		hugepage-size=Xm is the preferred way to set this to avoid
+		setting a non-pow-2 bad value.
 
 exitall		When one job finishes, terminate the rest. The default is
 		to wait for each job to finish, sometimes that is not the
@@ -403,7 +414,7 @@ create_serialize=bool	If true, serialize the file creating for the jobs.
 create_fsync=bool	fsync the data file after creation. This is the
 			default.
 
-unlink		Unlink the job files when done. fio defaults to doing this,
+unlink=bool	Unlink the job files when done. fio defaults to doing this,
 		if it created the file itself.
 
 loops=int	Run the specified number of iterations of this job. Used