X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;f=HOWTO;h=b61a638907334bdc7d8f84e77d2a23d979d69c54;hb=e155cb64ad042af42aafef26d1decf29c03e85d4;hp=406cfca0d3ba855e5261878d66ae9fcd7c976723;hpb=3a5db9201bf7b1717f63cb8f7dbd025903117f70;p=fio.git

diff --git a/HOWTO b/HOWTO
index 406cfca0..b61a6389 100644
--- a/HOWTO
+++ b/HOWTO
@@ -198,7 +198,7 @@ sections.
 -------------------------
 
 fio also supports environment variable expansion in job files. Any
-substring of the form "${VARNAME}" as part of an option value (in other
+sub-string of the form "${VARNAME}" as part of an option value (in other
 words, on the right of the `='), will be expanded to the value of the
 environment variable called VARNAME.  If no such environment variable
 is defined, or VARNAME is the empty string, the empty string will be
@@ -875,8 +875,8 @@ fsync=int	If writing to a file, issue a sync of the dirty data
 
 fdatasync=int	Like fsync= but uses fdatasync() to only sync data and not
 		metadata blocks.
-		In FreeBSD and Windows there is no fdatasync(), this falls back to
-		using fsync()
+		In FreeBSD and Windows there is no fdatasync(), this falls back
+		to using fsync()
 
 sync_file_range=str:val	Use sync_file_range() for every 'val' number of
 		write operations. Fio will track range of writes that
@@ -961,6 +961,8 @@ random_generator=str	Fio supports the following engines for generating
 
 		tausworthe	Strong 2^88 cycle random number generator
 		lfsr		Linear feedback shift register generator
+		tausworthe64	Strong 64-bit 2^258 cycle random number
+				generator
 
 		Tausworthe is a strong random number generator, but it
 		requires tracking on the side if we want to ensure that
@@ -1199,6 +1201,17 @@ create_only=bool	If true, fio will only run the setup phase of the job.
 			that will be done. The actual job contents are not
 			executed.
 
+allow_file_create=bool	If true, fio is permitted to create files as part
+		of its workload. This is the default behavior. If this
+		option is false, then fio will error out if the files it
+		needs to use don't already exist. Default: true.
+
+allow_mounted_write=bool	If this isn't set, fio will abort jobs that
+		are destructive (eg that write) to what appears to be a
+		mounted device or partition. This should help catch creating
+		inadvertently destructive tests, not realizing that the test
+		will destroy data on the mounted file system. Default: false.
+
 pre_read=bool	If this is given, files will be pre-read into memory before
 		starting the given IO operation. This will also clear
 		the 'invalidate' flag, since it is pointless to pre-read
@@ -1268,6 +1281,12 @@ verify=str	If writing to a file, fio can verify the file contents
 				verified for workloads that write data.
 				See also verify_pattern.
 
+			pattern	Verify a strict pattern. Normally fio includes
+				a header with some basic information and
+				checksumming, but if this option is set, only
+				the specific pattern set with 'verify_pattern'
+				is verified.
+
 			null	Only pretend to verify. Useful for testing
 				internals with ioengine=null, not for much
 				else.
@@ -1937,18 +1956,18 @@ Split up, the format is as follows:
 	terse version, fio version, jobname, groupid, error
 	READ status:
 		Total IO (KB), bandwidth (KB/sec), IOPS, runtime (msec)
-		Submission latency: min, max, mean, deviation (usec)
-		Completion latency: min, max, mean, deviation (usec)
+		Submission latency: min, max, mean, stdev (usec)
+		Completion latency: min, max, mean, stdev (usec)
 		Completion latency percentiles: 20 fields (see below)
-		Total latency: min, max, mean, deviation (usec)
-		Bw (KB/s): min, max, aggregate percentage of total, mean, deviation
+		Total latency: min, max, mean, stdev (usec)
+		Bw (KB/s): min, max, aggregate percentage of total, mean, stdev
 	WRITE status:
 		Total IO (KB), bandwidth (KB/sec), IOPS, runtime (msec)
-		Submission latency: min, max, mean, deviation (usec)
-		Completion latency: min, max, mean, deviation (usec)
+		Submission latency: min, max, mean, stdev (usec)
+		Completion latency: min, max, mean, stdev(usec)
 		Completion latency percentiles: 20 fields (see below)
-		Total latency: min, max, mean, deviation (usec)
-		Bw (KB/s): min, max, aggregate percentage of total, mean, deviation
+		Total latency: min, max, mean, stdev (usec)
+		Bw (KB/s): min, max, aggregate percentage of total, mean, stdev
 	CPU usage: user, system, context switches, major faults, minor faults
 	IO depths: <=1, 2, 4, 8, 16, 32, >=64
 	IO latencies microseconds: <=2, 4, 10, 20, 50, 100, 250, 500, 750, 1000