X-Git-Url: http://git.annexia.org/?a=blobdiff_plain;ds=inline;f=resize%2Fvirt-resize.pod;fp=resize%2Fvirt-resize.pod;h=8ae4894f59cb9800dd71ad94214e891da929fd70;hb=37cdd39ada139956f237b55c87c095bed622b5e3;hp=622d8b9154de77b23a09c51a9f0754e34f577598;hpb=5d8e4102b46158f323fb1f6d76a342edcb997b73;p=libguestfs.git
diff --git a/resize/virt-resize.pod b/resize/virt-resize.pod
index 622d8b9..8ae4894 100644
--- a/resize/virt-resize.pod
+++ b/resize/virt-resize.pod
@@ -246,6 +246,40 @@ C
)
Display help.
+=item B<--alignment N>
+
+Set the alignment of partitions to C sectors. The default in
+virt-resize E 1.13.19 was 64 sectors, and after that is 128
+sectors.
+
+Assuming 512 byte sector size inside the guest, here are some
+suitable values for this:
+
+=over 4
+
+=item I<--alignment 1> (512 bytes)
+
+The partitions would be packed together as closely as possible, but
+would be completely unaligned. In some cases this can cause very poor
+performance. See L for further details.
+
+=item I<--alignment 8> (4K)
+
+This would be the minimum acceptable alignment for reasonable
+performance on modern hosts.
+
+=item I<--alignment 128> (64K)
+
+This alignment provides good performance when the host is using high
+end network storage.
+
+=item I<--alignment 2048> (1M)
+
+This is the standard alignment used by all newly installed guests
+since around 2008.
+
+=back
+
=item B<-d>
=item B<--debug>
@@ -545,12 +579,12 @@ I<--machine-readable> option and will return an error.
=head2 "Partition 1 does not end on cylinder boundary."
-Virt-resize aligns partitions to multiples of 64 sectors. Usually
-this means the partitions will not be aligned to the ancient CHS
-geometry. However CHS geometry is meaningless for disks manufactured
-since the early 1990s, and doubly so for virtual hard drives.
-Alignment of partitions to cylinders is not required by any modern
-operating system.
+Virt-resize aligns partitions to multiples of 128 sectors (see the
+I<--alignment> parameter). Usually this means the partitions will not
+be aligned to the ancient CHS geometry. However CHS geometry is
+meaningless for disks manufactured since the early 1990s, and doubly
+so for virtual hard drives. Alignment of partitions to cylinders is
+not required by any modern operating system.
=head2 RESIZING WINDOWS VIRTUAL MACHINES
@@ -630,6 +664,7 @@ L,
L,
L,
L,
+L,
L.
=head1 AUTHOR