Move to stage3 only when remaining work can be done below max downtime.
To make sure the process will converge we will try only MAX_DIRTY_ITERATIONS.
Signed-off-by: Liran Schour <lir...@il.ibm.com>
---
block-migration.c | 67 +++++++++++++++++++++++++++++++++++-----------------
1 files changed, 45 insertions(+), 22 deletions(-)
diff --git a/block-migration.c b/block-migration.c
index 90c84b1..9ae04c4 100644
--- a/block-migration.c
+++ b/block-migration.c
@@ -17,6 +17,7 @@
#include "qemu-queue.h"
#include "monitor.h"
#include "block-migration.h"
+#include "migration.h"
#include <assert.h>
#define BLOCK_SIZE (BDRV_SECTORS_PER_DIRTY_CHUNK << BDRV_SECTOR_BITS)
@@ -30,6 +31,7 @@
#define BLOCKS_READ_CHANGE 100
#define INITIAL_BLOCKS_READ 100
#define MAX_DIRTY_ITERATIONS 100
+#define DISK_RATE (30 << 20) //30 MB/sec
//#define DEBUG_BLK_MIGRATION
@@ -135,10 +137,11 @@ static void blk_mig_read_cb(void *opaque, int ret)
blk->ret = ret;
QSIMPLEQ_INSERT_TAIL(&block_mig_state.blk_list, blk, entry);
-
+
block_mig_state.submitted--;
block_mig_state.read_done++;
assert(block_mig_state.submitted >= 0);
+
}
static int mig_save_device_bulk(Monitor *mon, QEMUFile *f,
@@ -225,7 +228,7 @@ static void init_blk_migration(Monitor *mon, QEMUFile *f)
block_mig_state.prev_progress = -1;
block_mig_state.bulk_completed = 0;
block_mig_state.dirty_iterations = 0;
-
+
for (bs = bdrv_first; bs != NULL; bs = bs->next) {
if (bs->type == BDRV_TYPE_HD) {
sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
@@ -405,15 +408,41 @@ static void flush_blks(QEMUFile* f)
block_mig_state.transferred);
}
-static int is_stage2_completed(void)
+static int64_t get_remaining_dirty(void)
{
+ BlkMigDevState *bmds;
+ int64_t dirty = 0;
+
+ QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
+ dirty += bdrv_get_dirty_count(bmds->bs);
+ }
+
+ return dirty;
+}
- if (block_mig_state.submitted == 0 &&
- block_mig_state.bulk_completed == 1) {
- return 1;
- } else {
- return 0;
+static int is_stage2_completed(void)
+{
+ int64_t remaining_dirty;
+
+ if (block_mig_state.bulk_completed == 1) {
+ if (block_mig_state.dirty_iterations++ > MAX_DIRTY_ITERATIONS) {
+ /* finish stage2 because we have too much dirty iterations */
+
+ return 1;
+ }
+
+ remaining_dirty = get_remaining_dirty();
+
+ if ((remaining_dirty * BLOCK_SIZE) * 1000000000 / DISK_RATE <=
+ migrate_max_downtime()) {
+ /* finish stage2 because we think that we can finish remaing work
+ below max_downtime */
+
+ return 1;
+ }
}
+
+ return 0;
}
static void blk_mig_cleanup(Monitor *mon)
@@ -438,9 +467,7 @@ static void blk_mig_cleanup(Monitor *mon)
}
static int block_save_live(Monitor *mon, QEMUFile *f, int stage, void *opaque)
-{
- int dirty_iteration = 0;
-
+{
dprintf("Enter save live stage %d submitted %d transferred %d\n",
stage, block_mig_state.submitted, block_mig_state.transferred);
@@ -482,19 +509,12 @@ static int block_save_live(Monitor *mon, QEMUFile *f, int
stage, void *opaque)
/* finish saving bulk on all devices */
block_mig_state.bulk_completed = 1;
}
- } else if (block_mig_state.dirty_iterations <
MAX_DIRTY_ITERATIONS) {
- if (dirty_iteration == 0) {
- /* increment dirty iteration only once per round */
- dirty_iteration = 1;
- block_mig_state.dirty_iterations++;
- }
+ } else {
+
if (blk_mig_save_dirty_block(mon, f, 1) == 0) {
/* no more dirty blocks */
break;
}
- } else {
- /* if we got here stop the loop */
- break;
}
}
@@ -507,9 +527,12 @@ static int block_save_live(Monitor *mon, QEMUFile *f, int
stage, void *opaque)
}
if (stage == 3) {
- /* we now for sure that save bulk is completed */
-
+ /* we know for sure that save bulk is completed and
+ all async read completed */
+ assert(block_mig_state.submitted == 0);
+
while(blk_mig_save_dirty_block(mon, f, 0) != 0);
+
blk_mig_cleanup(mon);
/* report completion */
--
1.5.2.4
