@@ -3179,7 +3179,7 @@ environment. This can be useful for testing or for disaster
recovery. You should be aware that interoperability may be
compromised by setting this value.
-These change can also be suppressed by adding
+These change can also be suppressed by adding
.B mdadm.imsm.test=1
to the kernel command line. This makes it easy to test IMSM
code in a virtual machine that doesn't have IMSM virtual hardware.
@@ -3454,6 +3454,25 @@ is any string. These names are supported by
since version 3.3 provided they are enabled in
.IR mdadm.conf .
+.SH UNDERSTANDING OUTPUT
+
+.TP
+EXAMINE
+
+.TP
+.B checkpoint
+Checkpoint value is reported when array is performing some action including
+resync, recovery or reshape. Checkpoints allow resuming action from certain
+point if it was interrupted.
+
+Checkpoint is reported as combination of two values: current migration unit
+and number of blocks per unit. By multiplying those values and dividing by
+array size checkpoint progress percentage can be obtained in relation to
+current progress reported in /proc/mdstat. Checkpoint is also related to (and
+sometimes based on) sysfs entry sync_completed but depending on action units
+may differ. Even if units are the same, it should not be expected that
+checkpoint and sync_completed will be exact match nor updated simultaneously.
+
.SH NOTE
.I mdadm
was previously known as
Add new section in man for explaining mdadm outputs. Describe checkpoint entry. Signed-off-by: Mateusz Kusiak <mateusz.kusiak@intel.com> --- mdadm.8.in | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-)