[PATCH docs 5/5] vzdump: document the start window

[Thomas Lamprecht <t.lamprecht@proxmox.com>]

Describe the new 'start-window' job option, and that it also ends
waiting for backup slots.

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
---
 vzdump.adoc | 20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/vzdump.adoc b/vzdump.adoc
index 6e65c29..d3ead93 100644
--- a/vzdump.adoc
+++ b/vzdump.adoc
@@ -351,7 +351,8 @@ time as other jobs that have it enabled, for example, a short hourly job
 alongside a long nightly one. Together, they stay within the backup concurrency
 of the node. A job without the option still runs alone, and while it waits for
 running jobs to finish, overlapping jobs that are due later do not start before
-it. Waiting for a free backup slot of the node is not limited by `lockwait`.
+it. Waiting for a free backup slot of the node is only limited by the start
+window, not by `lockwait`.
 
 If two running jobs include the same guest, the second one backs it up once the
 first one is done with it, waiting at most `lockwait` minutes.
@@ -361,6 +362,17 @@ example, a hook script that mounts a disk in the `job-start` phase and unmounts
 it in the `job-end` phase must not be used for overlapping jobs. With a job
 concurrency above one, the phases of different guests of a job overlap as well.
 
+Start Window
+~~~~~~~~~~~~
+
+The `start-window` job option ('Start Window' in the 'Advanced' tab) sets how
+many minutes after the scheduled start of a job guest backups may still begin.
+For manual backups, the window starts with the backup task. Guest backups
+running when the window ends finish normally, and guests that did not start in
+time are reported as skipped in the task log and in the notification. This
+keeps further guest backups from starting during business hours, also if a
+missed job is repeated later.
+
 Cluster-wide and Storage Limits
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
@@ -394,9 +406,9 @@ count separately, so use the cluster-wide limit to bound their sum.
 Guest backups get cluster-wide slots in the order they started waiting. One that
 waits for a storage at its limit lets others with room go first, but only a few
 times. A job has at most one guest waiting for cluster-wide slots at a time, and
-waits for them at most `lockwait` minutes in total. Like for node slots, waiting
-for free slots of a local storage is not limited by `lockwait`. The task log
-tells which limit a guest waits for.
+waits for them at most `lockwait` minutes in total, or until its start window
+ended. Like for node slots, waiting for free slots of a local storage is only
+limited by the start window. The task log tells which limit a guest waits for.
 To see which guest backups hold or wait for cluster-wide slots, use:
 
 ----
-- 
2.47.3