X-Git-Url: https://git.kernel.dk/?p=fio.git;a=blobdiff_plain;f=HOWTO;h=7a7d14ea0816080d794d25f4d899603e2eee57a8;hp=cdd6473b28f3574f7a8eca445715cb3d7156b93e;hb=a696fa2a9c2e21a1c88813235d6fc39d267f6155;hpb=0e92f873a3d542d2b237d68fd9391c92a85fa0b8

diff --git a/HOWTO b/HOWTO
index cdd6473b..7a7d14ea 100644
--- a/HOWTO
+++ b/HOWTO
@@ -203,7 +203,13 @@ $ncpus		Number of online available CPUs
 
 These can be used on the command line or in the job file, and will be
 automatically substituted with the current system values when the job
-is run.
+is run. Simple math is also supported on these keywords, so you can
+perform actions like:
+
+size=8*$mb_memory
+
+and get that properly expanded to 8 times the size of memory in the
+machine.
 
 
 5.0 Detailed list of parameters
@@ -988,6 +994,7 @@ gtod_cpu=int	Sometimes it's cheaper to dedicate a single thread of
 		for doing these time calls will be excluded from other
 		uses. Fio will manually clear it from the CPU mask of other
 		jobs.
+
 continue_on_error=bool	Normally fio will exit the job on the first observed
 		failure. If this option is set, fio will continue the job when
 		there is a 'non-fatal error' (EIO or EILSEQ) until the runtime
@@ -997,6 +1004,21 @@ continue_on_error=bool	Normally fio will exit the job on the first observed
 		given in the stats is the first error that was hit during the
 		run.
 
+cgroup_root=str	Root of the mounted blkio cgroup file systems. This is a Linux
+		specific IO controller. If your system doesn't have it mounted,
+		you can do so with:
+
+		# mount -t cgroup -o blkio none /cgroup
+
+		The cgroup_root defaults to /cgroup, if mounted elsewhere
+		please specify this option.
+
+cgroup=str	Add job to this control group. If it doesn't exist, it will
+		be created.
+
+cgroup_weight=int	Set the weight of the cgroup to this value. See
+		the documentation that comes with the kernel, allowed values
+		are in the range of 100..1000.
 
 6.0 Interpreting the output
 ---------------------------