8:39 a.m.
The default behavior while creating external checkpoints is to let the
guest run while the memory state is caputred. This leads to a larger
save file but minimizes the time needed to take the checkpoint.
This patch adds a flag that causes the guest to be paused before taking
the snapshot.
*include/libvirt/libvirt.h.in:
- add new paused reason: VIR_DOMAIN_PAUSED_SNAPSHOT
- add new flag for takin snapshot: VIR_DOMAIN_SNAPSHOT_CREATE_PAUSE
*tools/virsh-domain-monitor.c:
- add string representation for VIR_DOMAIN_PAUSED_SNAPSHOT
*tools/virsh-snapshot.c:
- add support for VIR_DOMAIN_SNAPSHOT_CREATE_PAUSE
*tools/virsh.pod:
- add docs for --pause option added to use
VIR_DOMAIN_SNAPSHOT_CREATE_PAUSE flag
---
include/libvirt/libvirt.h.in | 4 ++++
tools/virsh-domain-monitor.c | 2 ++
tools/virsh-snapshot.c | 6 ++++++
tools/virsh.pod | 12 ++++++++++--
4 files changed, 22 insertions(+), 2 deletions(-)
diff --git a/include/libvirt/libvirt.h.in b/include/libvirt/libvirt.h.in
index 81f12a4..376d6d5 100644
--- a/include/libvirt/libvirt.h.in
+++ b/include/libvirt/libvirt.h.in
@@ -179,6 +179,7 @@ typedef enum {
VIR_DOMAIN_PAUSED_WATCHDOG = 6, /* paused due to a watchdog event */
VIR_DOMAIN_PAUSED_FROM_SNAPSHOT = 7, /* paused after restoring from snapshot */
VIR_DOMAIN_PAUSED_SHUTTING_DOWN = 8, /* paused during shutdown process */
+ VIR_DOMAIN_PAUSED_SNAPSHOT = 9, /* paused while creating a snaphot */
#ifdef VIR_ENUM_SENTINELS
VIR_DOMAIN_PAUSED_LAST
@@ -3663,6 +3664,9 @@ typedef enum {
the domain */
VIR_DOMAIN_SNAPSHOT_CREATE_ATOMIC = (1 << 7), /* atomically avoid
partial changes */
+ VIR_DOMAIN_SNAPSHOT_CREATE_PAUSE = (1 << 8), /* pause the guest
+ before taking
+ checkpoint */
} virDomainSnapshotCreateFlags;
/* Take a snapshot of the current VM state */
diff --git a/tools/virsh-domain-monitor.c b/tools/virsh-domain-monitor.c
index b264f15..faf23fe 100644
--- a/tools/virsh-domain-monitor.c
+++ b/tools/virsh-domain-monitor.c
@@ -223,6 +223,8 @@ vshDomainStateReasonToString(int state, int reason)
return N_("from snapshot");
case VIR_DOMAIN_PAUSED_SHUTTING_DOWN:
return N_("shutting down");
+ case VIR_DOMAIN_PAUSED_SNAPSHOT:
+ return N_("creating snapshot");
case VIR_DOMAIN_PAUSED_UNKNOWN:
case VIR_DOMAIN_PAUSED_LAST:
;
diff --git a/tools/virsh-snapshot.c b/tools/virsh-snapshot.c
index b828371..05ee7bd 100644
--- a/tools/virsh-snapshot.c
+++ b/tools/virsh-snapshot.c
@@ -127,6 +127,7 @@ static const vshCmdOptDef opts_snapshot_create[] = {
{"reuse-external", VSH_OT_BOOL, 0, N_("reuse any existing external
files")},
{"quiesce", VSH_OT_BOOL, 0, N_("quiesce guest's file
systems")},
{"atomic", VSH_OT_BOOL, 0, N_("require atomic operation")},
+ {"pause", VSH_OT_BOOL, 0, N_("pause guest before taking
snapshot")},
{NULL, 0, 0, NULL}
};
@@ -155,6 +156,8 @@ cmdSnapshotCreate(vshControl *ctl, const vshCmd *cmd)
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_QUIESCE;
if (vshCommandOptBool(cmd, "atomic"))
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_ATOMIC;
+ if (vshCommandOptBool(cmd, "pause"))
+ flags |= VIR_DOMAIN_SNAPSHOT_CREATE_PAUSE;
dom = vshCommandOptDomain(ctl, cmd, NULL);
if (dom == NULL)
@@ -263,6 +266,7 @@ static const vshCmdOptDef opts_snapshot_create_as[] = {
{"reuse-external", VSH_OT_BOOL, 0, N_("reuse any existing external
files")},
{"quiesce", VSH_OT_BOOL, 0, N_("quiesce guest's file
systems")},
{"atomic", VSH_OT_BOOL, 0, N_("require atomic operation")},
+ {"pause", VSH_OT_BOOL, 0, N_("pause guest before taking
snapshot")},
{"diskspec", VSH_OT_ARGV, 0,
N_("disk attributes: disk[,snapshot=type][,driver=type][,file=name]")},
{NULL, 0, 0, NULL}
@@ -292,6 +296,8 @@ cmdSnapshotCreateAs(vshControl *ctl, const vshCmd *cmd)
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_QUIESCE;
if (vshCommandOptBool(cmd, "atomic"))
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_ATOMIC;
+ if (vshCommandOptBool(cmd, "pause"))
+ flags |= VIR_DOMAIN_SNAPSHOT_CREATE_PAUSE;
dom = vshCommandOptDomain(ctl, cmd, NULL);
if (dom == NULL)
diff --git a/tools/virsh.pod b/tools/virsh.pod
index ac8a00f..b02ca45 100644
--- a/tools/virsh.pod
+++ b/tools/virsh.pod
@@ -2575,7 +2575,7 @@ used to represent properties of snapshots.
=item B<snapshot-create> I<domain> [I<xmlfile>] {[I<--redefine>
[I<--current>]]
| [I<--no-metadata>] [I<--halt>] [I<--disk-only>]
[I<--reuse-external>]
-[I<--quiesce>] [I<--atomic>]}
+[I<--quiesce>] [I<--atomic>] [I<--pause>]}
Create a snapshot for domain I<domain> with the properties specified in
I<xmlfile>. Normally, the only properties settable for a domain snapshot
@@ -2628,6 +2628,10 @@ this. If this flag is not specified, then some hypervisors may
fail
after partially performing the action, and B<dumpxml> must be used to
see whether any partial changes occurred.
+If I<--pause> is specified, libvirt pauses the guest before taking the
+snapshot to decrease size of the memory image in case of external
+checkpoints. Afterwards the guest is resumed.
+
Existence of snapshot metadata will prevent attempts to B<undefine>
a persistent domain. However, for transient domains, snapshot
metadata is silently lost when the domain quits running (whether
@@ -2636,7 +2640,7 @@ by command such as B<destroy> or by internal guest action).
=item B<snapshot-create-as> I<domain> {[I<--print-xml>]
| [I<--no-metadata>] [I<--halt>] [I<--reuse-external>]}
[I<name>]
[I<description>] [I<--disk-only> [I<--quiesce>] [I<--atomic>]
-[[I<--diskspec>] B<diskspec>]...]
+[I<--pause>] [[I<--diskspec>] B<diskspec>]...]
Create a snapshot for domain I<domain> with the given <name> and
<description>; if either value is omitted, libvirt will choose a
@@ -2681,6 +2685,10 @@ this. If this flag is not specified, then some hypervisors may
fail
after partially performing the action, and B<dumpxml> must be used to
see whether any partial changes occurred.
+If I<--pause> is specified, libvirt pauses the guest before taking the
+snapshot to decrease size of the memory image in case of external
+checkpoints. Afterwards the guest is resumed.
+
=item B<snapshot-current> I<domain> {[I<--name>] |
[I<--security-info>]
| [I<snapshotname>]}
--
1.7.12