In order to sample real RAM, skip ramblock with size below MIN_RAMBLOCK_SIZE
which is set as 128M.
Signed-off-by: Chuan Zheng <zhengchuan@huawei.com>
Reviewed-by: David Edmondson <david.edmondson@oracle.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Li Qiang <liq3ea@gmail.com>
---
migration/dirtyrate.c | 21 +++++++++++++++++++++
migration/dirtyrate.h | 5 +++++
2 files changed, 26 insertions(+)
diff --git a/migration/dirtyrate.c b/migration/dirtyrate.c
index 68561af..ede8063 100644
--- a/migration/dirtyrate.c
+++ b/migration/dirtyrate.c
@@ -138,6 +138,18 @@ static void get_ramblock_dirty_info(RAMBlock *block,
strcpy(info->idstr, qemu_ram_get_idstr(block));
}
+static bool skip_sample_ramblock(RAMBlock *block)
+{
+ /*
+ * Sample only blocks larger than MIN_RAMBLOCK_SIZE.
+ */
+ if (qemu_ram_get_used_length(block) < (MIN_RAMBLOCK_SIZE << 10)) {
+ return true;
+ }
+
+ return false;
+}
+
static bool record_ramblock_hash_info(struct RamblockDirtyInfo **block_dinfo,
struct DirtyRateConfig config,
int *block_count)
@@ -150,6 +162,9 @@ static bool record_ramblock_hash_info(struct RamblockDirtyInfo **block_dinfo,
bool ret = false;
RAMBLOCK_FOREACH_MIGRATABLE(block) {
+ if (skip_sample_ramblock(block)) {
+ continue;
+ }
total_count++;
}
@@ -159,6 +174,9 @@ static bool record_ramblock_hash_info(struct RamblockDirtyInfo **block_dinfo,
}
RAMBLOCK_FOREACH_MIGRATABLE(block) {
+ if (skip_sample_ramblock(block)) {
+ continue;
+ }
if (index >= total_count) {
break;
}
@@ -225,6 +243,9 @@ static bool compare_page_hash_info(struct RamblockDirtyInfo *info,
RAMBlock *block = NULL;
RAMBLOCK_FOREACH_MIGRATABLE(block) {
+ if (skip_sample_ramblock(block)) {
+ continue;
+ }
block_dinfo = find_block_matched(block, block_count, info);
if (block_dinfo == NULL) {
continue;
diff --git a/migration/dirtyrate.h b/migration/dirtyrate.h
index a3ee305..faaf9da 100644
--- a/migration/dirtyrate.h
+++ b/migration/dirtyrate.h
@@ -24,6 +24,11 @@
*/
#define RAMBLOCK_INFO_MAX_LEN 256
+/*
+ * Minimum RAMBlock size to sample, in megabytes.
+ */
+#define MIN_RAMBLOCK_SIZE 128
+
struct DirtyRateConfig {
uint64_t sample_pages_per_gigabytes; /* sample pages per GB */
int64_t sample_period_seconds; /* time duration between two sampling */
--
1.8.3.1