Update extent size information in vgchange and vgcreate man pages

WHATS_NEW

@@ -1,5 +1,6 @@
 Version 2.02.03 - 
 ===================================
+  Update extent size information in vgchange and vgcreate man pages.
   Introduce origin_from_cow().
   pvremove without -f now fails if there's no PV label.
   Support lvconvert -s.

man/vgchange.8

@@ -17,6 +17,8 @@ vgchange \- change attributes of a volume group
 .RB [ \-l | \-\-logicalvolume
 .IR MaxLogicalVolumes ]
 .RB [ \-P | \-\-partial]
+.RB [ \-s | \-\-physicalextentsize
+.IR PhysicalExtentSize [ \fBkKmMgGtT\fR ]]
 .RB [ -t | \-\-test]
 .RB [ \-v | \-\-verbose]
 .RB [ \-\-version ]
@@ -59,6 +61,27 @@ exclusively because they can only be used on one node at once.
 Changes the maximum logical volume number of an existing inactive
 volume group.
 .TP
+.BR \-s ", " \-\-physicalextentsize " " \fIPhysicalExtentSize\fR[\fBkKmMgGtT\fR]
+Changes the physical extent size on physical volumes of this volume group.
+A size suffix (k for kilobytes up to t for terabytes) is optional, megabytes
+is the default if no suffix is present.
+The default is 4 MB and it must be at least 1 KB and a power of 2.
+ 
+Before increasing the physical extent size, you might need to use lvresize,
+pvresize and/or pvmove so that everything fits.  For example, every
+contiguous range of extents used in a logical volume must start and 
+end on an extent boundary.
+ 
+If the volume group metadata uses lvm1 format, extents can vary in size from
+8KB to 16GB and there is a limit of 65534 extents in each logical volume.  The
+default of 4 MB leads to a maximum logical volume size of around 256GB.
+ 
+If the volume group metadata uses lvm2 format those restrictions do not apply,
+but having a large number of extents will slow down the tools but have no
+impact on I/O performance to the logical volume.  The smallest PE is 1KB.
+ 
+The 2.4 kernel has a limitation of 2TB per block device.
+.TP
 .BR \-x ", " \-\-resizeable { y | n }
 Enables or disables the extension/reduction of this volume group
 with/by physical volumes.

man/vgcreate.8

@@ -59,17 +59,22 @@ as described in \fBpvcreate(8)\fP.
 .BR \-s ", " \-\-physicalextentsize " " \fIPhysicalExtentSize\fR[\fBkKmMgGtT\fR]
 Sets the physical extent size on physical volumes of this volume group.
 A size suffix (k for kilobytes up to t for terabytes) is optional, megabytes
-is the default if no suffix is present.  Values can be from 8 KB to 16 GB in
+is the default if no suffix is present.  
-powers of 2.  The default is 4 MB.
+The default is 4 MB and it must be at least 1 KB and a power of 2.
+
 Once this value has been set, it is difficult to change it without recreating
 the volume group which would involve backing up and restoring data on any 
-logical volumes.
+logical volumes.  However, if no extents need moving for the new
-If the volume group metadata uses lvm1 format, there is a limit of 65534
+value to apply, it can be altered using vgchange \-s.
-extents in each logical volume, so the default of 4 MB leads to a maximum 
+
-logical volume size of around 256GB.
+If the volume group metadata uses lvm1 format, extents can vary in size from
-If the volume group metadata uses lvm2 format there is no such restriction,
+8KB to 16GB and there is a limit of 65534 extents in each logical volume.  The
-although having a large number of extents will slow down
+default of 4 MB leads to a maximum logical volume size of around 256GB.  
-the tools but have no impact on I/O performance to the logical volume.
+
+If the volume group metadata uses lvm2 format those restrictions do not apply,
+but having a large number of extents will slow down the tools but have no
+impact on I/O performance to the logical volume.  The smallest PE is 1KB.
+
 The 2.4 kernel has a limitation of 2TB per block device.
 .SH EXAMPLES
 To create a volume group named