Signed-off-by: Fabian Grünbichler <f.gruenbich...@proxmox.com>
---
Notes:
not sure whether we want to also add a note suggesting to (heavily)
overprovision the LUN/backing device on the storage side, so that there is
enough "space" for creating snapshots?
pve-storage-lvm.adoc | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/pve-storage-lvm.adoc b/pve-storage-lvm.adoc
index 6928330..c508fe1 100644
--- a/pve-storage-lvm.adoc
+++ b/pve-storage-lvm.adoc
@@ -57,8 +57,7 @@ snapshot's name and starts a new volume backed by the
snapshot.
+
A volume based on a snapshot references its parent snapshot volume as its
backing volume and records only the differences to that backing volume.
-Snapshot volumes are currently thick-provisioned LVM logical volumes, but the
-underlying block storage may provide thin provisioning.
+Snapshot volumes are currently thick-provisioned LVM logical volumes.
+
This design avoids issues with native LVM snapshots, such as significant
input/output (I/O) penalties and unexpected, dangerous behavior when running
out
@@ -74,6 +73,11 @@ functionality.
The snapshot functionality is managed by the PVE storage system.
+
Enabling or disabling this flag only affects newly created virtual disk
volumes.
++
+For efficient support of `snapshot-as-volume-chain`, the backing storage must
+support thin-provisioning and discard. Each snapshot will appear to use the
+full volume size on the PVE side, but the actual space usage on the underlying
+storage will be smaller if those requirements are met.
.Configuration Example (`/etc/pve/storage.cfg`)
----
--
2.39.5
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