> On Wed, May 11, 2011 at 8:58 AM, Shribman, Aidan
> <aidan.shrib...@sap.com> wrote:
> > From: Aidan Shribman <aidan.shrib...@sap.com>
> >
> > [PATCH] Add warmup phase for live migration of large memory apps
> >
> > By invoking "migrate -w <url>" we initiate a background
> live-migration
> > transferring of dirty pages continuously until invocation
> of "migrate_end"
> > which attempts to complete the live migration operation.
>
> What is the purpose of this patch? How and when do I use it?
>
The warmup patch adds none-converging background update of guest memory during
live-migration such that on request of live-migration completion (via
"migrate_end" command) we get much faster response. This is especially needed
when running a payload of large enterprise applications which have high memory
demands.
> Some nitpicks:
>
> > @@ -81,6 +83,11 @@ int do_migrate(Monitor *mon, const QDict
> *qdict, QObject **ret_data)
> > int blk = qdict_get_try_bool(qdict, "blk", 0);
> > int inc = qdict_get_try_bool(qdict, "inc", 0);
> > const char *uri = qdict_get_str(qdict, "uri");
> > + is_migrate_warmup = qdict_get_try_bool(qdict, "warmup", 0);
> > +
> > + if (is_migrate_warmup) {
> > + detach = 1; /* as we need migrate_end to complte */
>
> s/complte/complete/
>
> > + }
>
> Please follow the coding style and put the closing curly brace on the
> same column as the 'if' statement.
>
> > +int qemu_savevm_state_warmup(Monitor *mon, QEMUFile *f) {
> > + int ret = 1;
>
> 1 is overwritten immediately.
A new patch follows with corrections:
---
From: Aidan Shribman <aidan.shrib...@sap.com>
Subject: Add warmup phase for live migration of large memory apps
By invoking "migrate -w <url>" we initiate a background live-migration
transferring of dirty pages continuously until invocation of "migrate_end"
which attempts to complete the live migration operation.
Qemu host: Ubuntu 10.10
Testing: live migration (with/without warmup phase) tested successfully.
Signed-off-by: Benoit Hudzia <benoit.hud...@sap.com>
Signed-off-by: Petter Svard <pett...@cs.umu.se>
Signed-off-by: Aidan Shribman <aidan.shrib...@sap.com>
---
hmp-commands.hx | 33 +++++++++++++++++++++++++--------
migration.c | 23 ++++++++++++++++++++++-
migration.h | 2 ++
qmp-commands.hx | 41 ++++++++++++++++++++++++++++++++++-------
savevm.c | 11 +++++++++++
sysemu.h | 1 +
6 files changed, 95 insertions(+), 16 deletions(-)
diff --git a/hmp-commands.hx b/hmp-commands.hx
index e5585ba..215ea41 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -717,24 +717,28 @@ ETEXI
{
.name = "migrate",
- .args_type = "detach:-d,blk:-b,inc:-i,uri:s",
- .params = "[-d] [-b] [-i] uri",
- .help = "migrate to URI (using -d to not wait for completion)"
- "\n\t\t\t -b for migration without shared storage with"
- " full copy of disk\n\t\t\t -i for migration without "
- "shared storage with incremental copy of disk "
- "(base image shared between src and destination)",
+ .args_type = "detach:-d,blk:-b,inc:-i,warmup:-w,uri:s",
+ .params = "[-d] [-b] [-i] [-w] uri",
+ .help = "migrate to URI"
+ "\n\t -d to not wait for completion"
+ "\n\t -b for migration without shared storage with"
+ " full copy of disk"
+ "\n\t -i for migration without"
+ " shared storage with incremental copy of disk"
+ " (base image shared between source and destination)"
+ "\n\t -w to enter warmup phase",
.user_print = monitor_user_noop,
.mhandler.cmd_new = do_migrate,
},
STEXI
-@item migrate [-d] [-b] [-i] @var{uri}
+@item migrate [-d] [-b] [-i] [-w] @var{uri}
@findex migrate
Migrate to @var{uri} (using -d to not wait for completion).
-b for migration with full copy of disk
-i for migration with incremental copy of disk (base image is shared)
+ -w to enter warmup phase
ETEXI
{
@@ -753,6 +757,19 @@ Cancel the current VM migration.
ETEXI
{
+ .name = "migrate_end",
+ .args_type = "",
+ .params = "",
+ .help = "Complete warmup and move to full live migration",
+ .mhandler.cmd = do_migrate_end,
+ },
+
+STEXI
+@item migrate_end
+Complete warmup and move to full live migration.
+ETEXI
+
+ {
.name = "migrate_set_speed",
.args_type = "value:o",
.params = "value",
diff --git a/migration.c b/migration.c
index 9ee8b17..c178a77 100644
--- a/migration.c
+++ b/migration.c
@@ -31,6 +31,8 @@
do { } while (0)
#endif
+static int is_migrate_warmup = 0;
+
/* Migration speed throttling */
static uint32_t max_throttle = (32 << 20);
@@ -81,6 +83,11 @@ int do_migrate(Monitor *mon, const QDict *qdict, QObject
**ret_data)
int blk = qdict_get_try_bool(qdict, "blk", 0);
int inc = qdict_get_try_bool(qdict, "inc", 0);
const char *uri = qdict_get_str(qdict, "uri");
+ is_migrate_warmup = qdict_get_try_bool(qdict, "warmup", 0);
+
+ if (is_migrate_warmup) {
+ detach = 1; /* as we need migrate_end to complete */
+ }
if (current_migration &&
current_migration->get_status(current_migration) == MIG_STATE_ACTIVE) {
@@ -361,7 +368,9 @@ void migrate_fd_put_ready(void *opaque)
}
DPRINTF("iterate\n");
- if (qemu_savevm_state_iterate(s->mon, s->file) == 1) {
+ if (is_migrate_warmup) {
+ qemu_savevm_state_warmup(s->mon, s->file);
+ } else if (qemu_savevm_state_iterate(s->mon, s->file) == 1) {
int state;
int old_vm_running = vm_running;
@@ -448,3 +457,15 @@ int migrate_fd_close(void *opaque)
qemu_set_fd_handler2(s->fd, NULL, NULL, NULL, NULL);
return s->close(s);
}
+
+void do_migrate_end(Monitor *mon, const QDict *qdict)
+{
+ if (!vm_running) {
+ return;
+ }
+ if (!is_migrate_warmup) {
+ return;
+ }
+ is_migrate_warmup = 0;
+}
+
diff --git a/migration.h b/migration.h
index d13ed4f..6a96b29 100644
--- a/migration.h
+++ b/migration.h
@@ -134,4 +134,6 @@ static inline FdMigrationState
*migrate_to_fms(MigrationState *mig_state)
return container_of(mig_state, FdMigrationState, mig_state);
}
+void do_migrate_end(Monitor *mon, const QDict *qdict);
+
#endif
diff --git a/qmp-commands.hx b/qmp-commands.hx
index 793cf1c..1f85c09 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -431,13 +431,16 @@ EQMP
{
.name = "migrate",
- .args_type = "detach:-d,blk:-b,inc:-i,uri:s",
- .params = "[-d] [-b] [-i] uri",
- .help = "migrate to URI (using -d to not wait for completion)"
- "\n\t\t\t -b for migration without shared storage with"
- " full copy of disk\n\t\t\t -i for migration without "
- "shared storage with incremental copy of disk "
- "(base image shared between src and destination)",
+ .args_type = "detach:-d,blk:-b,inc:-i,xbrle:-x,warmup:-w,uri:s",
+ .params = "[-d] [-b] [-i] [-w] uri",
+ .help = "migrate to URI"
+ "\n\t -d to not wait for completion"
+ "\n\t -b for migration without shared storage with"
+ " full copy of disk"
+ "\n\t -i for migration without"
+ " shared storage with incremental copy of disk"
+ " (base image shared between source and destination)"
+ "\n\t -w to enter warmup phase",
.user_print = monitor_user_noop,
.mhandler.cmd_new = do_migrate,
},
@@ -453,6 +456,7 @@ Arguments:
- "blk": block migration, full disk copy (json-bool, optional)
- "inc": incremental disk copy (json-bool, optional)
- "uri": Destination URI (json-string)
+- "warmup": to enter warmup phase
Example:
@@ -494,6 +498,29 @@ Example:
EQMP
{
+ .name = "migrate_end",
+ .args_type = "",
+ .params = "",
+ .help = "Complete warmup and move to full live migration",
+ .mhandler.cmd = do_migrate_end,
+ },
+
+SQMP
+migrate_end
+-----------
+
+End the current migration warmup.
+
+Arguments: None.
+
+Example:
+
+-> { "execute": "migrate_end" }
+<- { "return": {} }
+
+EQMP
+
+ {
.name = "migrate_set_speed",
.args_type = "value:f",
.params = "value",
diff --git a/savevm.c b/savevm.c
index 4e49765..425c7b7 100644
--- a/savevm.c
+++ b/savevm.c
@@ -1471,6 +1471,17 @@ int qemu_savevm_state_begin(Monitor *mon, QEMUFile *f,
int blk_enable,
return 0;
}
+int qemu_savevm_state_warmup(Monitor *mon, QEMUFile *f)
+{
+ int ret;
+
+ if ((ret = qemu_savevm_state_iterate(mon, f)) < 0) {
+ return ret;
+ }
+
+ return 0;
+}
+
int qemu_savevm_state_iterate(Monitor *mon, QEMUFile *f)
{
SaveStateEntry *se;
diff --git a/sysemu.h b/sysemu.h
index b81a70e..74e8a48 100644
--- a/sysemu.h
+++ b/sysemu.h
@@ -76,6 +76,7 @@ void main_loop_wait(int nonblocking);
int qemu_savevm_state_begin(Monitor *mon, QEMUFile *f, int blk_enable,
int shared);
int qemu_savevm_state_iterate(Monitor *mon, QEMUFile *f);
+int qemu_savevm_state_warmup(Monitor *mon, QEMUFile *f);
int qemu_savevm_state_complete(Monitor *mon, QEMUFile *f);
void qemu_savevm_state_cancel(Monitor *mon, QEMUFile *f);
int qemu_loadvm_state(QEMUFile *f);
---
