migration/block.c | 38 ++++++++++++++++++++++++++++++++++++-- 1 file changed, 36 insertions(+), 2 deletions(-)
From: Lidong Chen <lidongchen@tencent.com>
BLOCK_SIZE is (1 << 20), qcow2 cluster size is 65536 by default,
this maybe cause the qcow2 file size is bigger after migration.
This patch check each cluster, use blk_pwrite_zeroes for each
zero cluster.
Signed-off-by: Lidong Chen <lidongchen@tencent.com>
---
migration/block.c | 38 ++++++++++++++++++++++++++++++++++++--
1 file changed, 36 insertions(+), 2 deletions(-)
diff --git a/migration/block.c b/migration/block.c
index 7734ff7..fe613db 100644
--- a/migration/block.c
+++ b/migration/block.c
@@ -885,6 +885,8 @@ static int block_load(QEMUFile *f, void *opaque, int version_id)
int64_t total_sectors = 0;
int nr_sectors;
int ret;
+ BlockDriverInfo bdi;
+ int cluster_size;
do {
addr = qemu_get_be64(f);
@@ -934,8 +936,40 @@ static int block_load(QEMUFile *f, void *opaque, int version_id)
} else {
buf = g_malloc(BLOCK_SIZE);
qemu_get_buffer(f, buf, BLOCK_SIZE);
- ret = blk_pwrite(blk, addr * BDRV_SECTOR_SIZE, buf,
- nr_sectors * BDRV_SECTOR_SIZE, 0);
+
+ ret = bdrv_get_info(blk_bs(blk), &bdi);
+ cluster_size = bdi.cluster_size;
+
+ if (ret == 0 && cluster_size > 0 &&
+ cluster_size <= BLOCK_SIZE &&
+ BLOCK_SIZE % cluster_size == 0) {
+ int i;
+ int64_t cur_addr;
+ uint8_t *cur_buf;
+
+ for (i = 0; i < BLOCK_SIZE / cluster_size; i++) {
+ cur_addr = addr * BDRV_SECTOR_SIZE
+ + i * cluster_size;
+ cur_buf = buf + i * cluster_size;
+
+ if (buffer_is_zero(cur_buf, cluster_size)) {
+ ret = blk_pwrite_zeroes(blk, cur_addr,
+ cluster_size,
+ BDRV_REQ_MAY_UNMAP);
+ } else {
+ ret = blk_pwrite(blk, cur_addr, cur_buf,
+ cluster_size, 0);
+ }
+
+ if (ret < 0) {
+ g_free(buf);
+ return ret;
+ }
+ }
+ } else {
+ ret = blk_pwrite(blk, addr * BDRV_SECTOR_SIZE, buf,
+ nr_sectors * BDRV_SECTOR_SIZE, 0);
+ }
g_free(buf);
}
--
1.8.3.1
On Sun, 04/09 20:37, jemmy858585@gmail.com wrote:
> From: Lidong Chen <lidongchen@tencent.com>
>
> BLOCK_SIZE is (1 << 20), qcow2 cluster size is 65536 by default,
> this maybe cause the qcow2 file size is bigger after migration.
> This patch check each cluster, use blk_pwrite_zeroes for each
> zero cluster.
>
> Signed-off-by: Lidong Chen <lidongchen@tencent.com>
> ---
> migration/block.c | 38 ++++++++++++++++++++++++++++++++++++--
> 1 file changed, 36 insertions(+), 2 deletions(-)
>
> diff --git a/migration/block.c b/migration/block.c
> index 7734ff7..fe613db 100644
> --- a/migration/block.c
> +++ b/migration/block.c
> @@ -885,6 +885,8 @@ static int block_load(QEMUFile *f, void *opaque, int version_id)
> int64_t total_sectors = 0;
> int nr_sectors;
> int ret;
> + BlockDriverInfo bdi;
> + int cluster_size;
>
> do {
> addr = qemu_get_be64(f);
> @@ -934,8 +936,40 @@ static int block_load(QEMUFile *f, void *opaque, int version_id)
> } else {
> buf = g_malloc(BLOCK_SIZE);
> qemu_get_buffer(f, buf, BLOCK_SIZE);
> - ret = blk_pwrite(blk, addr * BDRV_SECTOR_SIZE, buf,
> - nr_sectors * BDRV_SECTOR_SIZE, 0);
> +
> + ret = bdrv_get_info(blk_bs(blk), &bdi);
> + cluster_size = bdi.cluster_size;
> +
> + if (ret == 0 && cluster_size > 0 &&
> + cluster_size <= BLOCK_SIZE &&
> + BLOCK_SIZE % cluster_size == 0) {
> + int i;
> + int64_t cur_addr;
> + uint8_t *cur_buf;
> +
> + for (i = 0; i < BLOCK_SIZE / cluster_size; i++) {
> + cur_addr = addr * BDRV_SECTOR_SIZE
> + + i * cluster_size;
> + cur_buf = buf + i * cluster_size;
> +
> + if (buffer_is_zero(cur_buf, cluster_size)) {
> + ret = blk_pwrite_zeroes(blk, cur_addr,
> + cluster_size,
> + BDRV_REQ_MAY_UNMAP);
> + } else {
> + ret = blk_pwrite(blk, cur_addr, cur_buf,
> + cluster_size, 0);
> + }
> +
> + if (ret < 0) {
> + g_free(buf);
> + return ret;
> + }
This if block is not necessary because...
> + }
> + } else {
> + ret = blk_pwrite(blk, addr * BDRV_SECTOR_SIZE, buf,
> + nr_sectors * BDRV_SECTOR_SIZE, 0);
> + }
> g_free(buf);
...
if (ret < 0) {
return ret;
}
> }
>
> --
> 1.8.3.1
>
>
If you remove that:
Reviewed-by: Fam Zheng <famz@redhat.com>
On Mon, Apr 10, 2017 at 8:51 AM, Fam Zheng <famz@redhat.com> wrote:
> On Sun, 04/09 20:37, jemmy858585@gmail.com wrote:
>> From: Lidong Chen <lidongchen@tencent.com>
>>
>> BLOCK_SIZE is (1 << 20), qcow2 cluster size is 65536 by default,
>> this maybe cause the qcow2 file size is bigger after migration.
>> This patch check each cluster, use blk_pwrite_zeroes for each
>> zero cluster.
>>
>> Signed-off-by: Lidong Chen <lidongchen@tencent.com>
>> ---
>> migration/block.c | 38 ++++++++++++++++++++++++++++++++++++--
>> 1 file changed, 36 insertions(+), 2 deletions(-)
>>
>> diff --git a/migration/block.c b/migration/block.c
>> index 7734ff7..fe613db 100644
>> --- a/migration/block.c
>> +++ b/migration/block.c
>> @@ -885,6 +885,8 @@ static int block_load(QEMUFile *f, void *opaque, int version_id)
>> int64_t total_sectors = 0;
>> int nr_sectors;
>> int ret;
>> + BlockDriverInfo bdi;
>> + int cluster_size;
>>
>> do {
>> addr = qemu_get_be64(f);
>> @@ -934,8 +936,40 @@ static int block_load(QEMUFile *f, void *opaque, int version_id)
>> } else {
>> buf = g_malloc(BLOCK_SIZE);
>> qemu_get_buffer(f, buf, BLOCK_SIZE);
>> - ret = blk_pwrite(blk, addr * BDRV_SECTOR_SIZE, buf,
>> - nr_sectors * BDRV_SECTOR_SIZE, 0);
>> +
>> + ret = bdrv_get_info(blk_bs(blk), &bdi);
>> + cluster_size = bdi.cluster_size;
>> +
>> + if (ret == 0 && cluster_size > 0 &&
>> + cluster_size <= BLOCK_SIZE &&
>> + BLOCK_SIZE % cluster_size == 0) {
>> + int i;
>> + int64_t cur_addr;
>> + uint8_t *cur_buf;
>> +
>> + for (i = 0; i < BLOCK_SIZE / cluster_size; i++) {
>> + cur_addr = addr * BDRV_SECTOR_SIZE
>> + + i * cluster_size;
>> + cur_buf = buf + i * cluster_size;
>> +
>> + if (buffer_is_zero(cur_buf, cluster_size)) {
>> + ret = blk_pwrite_zeroes(blk, cur_addr,
>> + cluster_size,
>> + BDRV_REQ_MAY_UNMAP);
>> + } else {
>> + ret = blk_pwrite(blk, cur_addr, cur_buf,
>> + cluster_size, 0);
>> + }
>> +
>> + if (ret < 0) {
>> + g_free(buf);
>> + return ret;
>> + }
>
> This if block is not necessary because...
Hi Fam:
It's necessary to check each cluster is written successfully.
if we remove this if block, it maybe ignore some error, and only check
the last cluster.
Thanks.
>
>> + }
>> + } else {
>> + ret = blk_pwrite(blk, addr * BDRV_SECTOR_SIZE, buf,
>> + nr_sectors * BDRV_SECTOR_SIZE, 0);
>> + }
>> g_free(buf);
> ...
>
>
> if (ret < 0) {
> return ret;
> }
>> }
>>
>> --
>> 1.8.3.1
>>
>>
>
> If you remove that:
>
> Reviewed-by: Fam Zheng <famz@redhat.com>
On Mon, 04/10 09:10, 858585 jemmy wrote:
> >> + if (ret < 0) {
> >> + g_free(buf);
> >> + return ret;
> >> + }
> >
> > This if block is not necessary because...
>
> Hi Fam:
> It's necessary to check each cluster is written successfully.
> if we remove this if block, it maybe ignore some error, and only check
> the last cluster.
> Thanks.
Yes, I missed the fact it is in the loop body. My bad. Thanks for pointint out:
Reviewed-by: Fam Zheng <famz@redhat.com>
On Sun, Apr 09, 2017 at 08:37:40PM +0800, jemmy858585@gmail.com wrote:
> From: Lidong Chen <lidongchen@tencent.com>
>
> BLOCK_SIZE is (1 << 20), qcow2 cluster size is 65536 by default,
> this maybe cause the qcow2 file size is bigger after migration.
> This patch check each cluster, use blk_pwrite_zeroes for each
> zero cluster.
>
> Signed-off-by: Lidong Chen <lidongchen@tencent.com>
> ---
> migration/block.c | 38 ++++++++++++++++++++++++++++++++++++--
> 1 file changed, 36 insertions(+), 2 deletions(-)
>
> diff --git a/migration/block.c b/migration/block.c
> index 7734ff7..fe613db 100644
> --- a/migration/block.c
> +++ b/migration/block.c
> @@ -885,6 +885,8 @@ static int block_load(QEMUFile *f, void *opaque, int version_id)
> int64_t total_sectors = 0;
> int nr_sectors;
> int ret;
> + BlockDriverInfo bdi;
> + int cluster_size;
>
> do {
> addr = qemu_get_be64(f);
> @@ -934,8 +936,40 @@ static int block_load(QEMUFile *f, void *opaque, int version_id)
> } else {
> buf = g_malloc(BLOCK_SIZE);
> qemu_get_buffer(f, buf, BLOCK_SIZE);
> - ret = blk_pwrite(blk, addr * BDRV_SECTOR_SIZE, buf,
> - nr_sectors * BDRV_SECTOR_SIZE, 0);
> +
> + ret = bdrv_get_info(blk_bs(blk), &bdi);
> + cluster_size = bdi.cluster_size;
> +
> + if (ret == 0 && cluster_size > 0 &&
> + cluster_size <= BLOCK_SIZE &&
> + BLOCK_SIZE % cluster_size == 0) {
How about:
if (blk != blk_prev) {
blk_prev = blk;
total_sectors = blk_nb_sectors(blk);
if (total_sectors <= 0) {
error_report("Error getting length of block device %s",
device_name);
return -EINVAL;
}
blk_invalidate_cache(blk, &local_err);
if (local_err) {
error_report_err(local_err);
return -EINVAL;
}
+ ret = bdrv_get_info(blk_bs(blk), &bdi);
+ if (ret == 0 && cluster_size > 0 && cluster_size <= BLOCK_SIZE &&
+ BLOCK_SIZE % cluster_size == 0) {
+ zero_cluster_size = bdi.cluster_size;
+ } else {
+ zero_cluster_size = 0;
+ }
}
That way we only fetch the cluster size once per device.
When processing a block we do without repeatedly fetching the cluster
size:
if (zero_cluster_size) {
...detect zeroes...
}
> + int i;
> + int64_t cur_addr;
> + uint8_t *cur_buf;
> +
> + for (i = 0; i < BLOCK_SIZE / cluster_size; i++) {
> + cur_addr = addr * BDRV_SECTOR_SIZE
> + + i * cluster_size;
> + cur_buf = buf + i * cluster_size;
> +
> + if (buffer_is_zero(cur_buf, cluster_size)) {
> + ret = blk_pwrite_zeroes(blk, cur_addr,
> + cluster_size,
> + BDRV_REQ_MAY_UNMAP);
> + } else {
> + ret = blk_pwrite(blk, cur_addr, cur_buf,
> + cluster_size, 0);
Indentation is off here.
> + }
> +
> + if (ret < 0) {
> + g_free(buf);
> + return ret;
> + }
> + }
> + } else {
> + ret = blk_pwrite(blk, addr * BDRV_SECTOR_SIZE, buf,
> + nr_sectors * BDRV_SECTOR_SIZE, 0);
> + }
> g_free(buf);
> }
>
> --
> 1.8.3.1
>
On Tue, Apr 11, 2017 at 12:00 AM, Stefan Hajnoczi <stefanha@redhat.com> wrote:
> On Sun, Apr 09, 2017 at 08:37:40PM +0800, jemmy858585@gmail.com wrote:
>> From: Lidong Chen <lidongchen@tencent.com>
>>
>> BLOCK_SIZE is (1 << 20), qcow2 cluster size is 65536 by default,
>> this maybe cause the qcow2 file size is bigger after migration.
>> This patch check each cluster, use blk_pwrite_zeroes for each
>> zero cluster.
>>
>> Signed-off-by: Lidong Chen <lidongchen@tencent.com>
>> ---
>> migration/block.c | 38 ++++++++++++++++++++++++++++++++++++--
>> 1 file changed, 36 insertions(+), 2 deletions(-)
>>
>> diff --git a/migration/block.c b/migration/block.c
>> index 7734ff7..fe613db 100644
>> --- a/migration/block.c
>> +++ b/migration/block.c
>> @@ -885,6 +885,8 @@ static int block_load(QEMUFile *f, void *opaque, int version_id)
>> int64_t total_sectors = 0;
>> int nr_sectors;
>> int ret;
>> + BlockDriverInfo bdi;
>> + int cluster_size;
>>
>> do {
>> addr = qemu_get_be64(f);
>> @@ -934,8 +936,40 @@ static int block_load(QEMUFile *f, void *opaque, int version_id)
>> } else {
>> buf = g_malloc(BLOCK_SIZE);
>> qemu_get_buffer(f, buf, BLOCK_SIZE);
>> - ret = blk_pwrite(blk, addr * BDRV_SECTOR_SIZE, buf,
>> - nr_sectors * BDRV_SECTOR_SIZE, 0);
>> +
>> + ret = bdrv_get_info(blk_bs(blk), &bdi);
>> + cluster_size = bdi.cluster_size;
>> +
>> + if (ret == 0 && cluster_size > 0 &&
>> + cluster_size <= BLOCK_SIZE &&
>> + BLOCK_SIZE % cluster_size == 0) {
>
> How about:
>
> if (blk != blk_prev) {
> blk_prev = blk;
> total_sectors = blk_nb_sectors(blk);
> if (total_sectors <= 0) {
> error_report("Error getting length of block device %s",
> device_name);
> return -EINVAL;
> }
>
> blk_invalidate_cache(blk, &local_err);
> if (local_err) {
> error_report_err(local_err);
> return -EINVAL;
> }
>
> + ret = bdrv_get_info(blk_bs(blk), &bdi);
> + if (ret == 0 && cluster_size > 0 && cluster_size <= BLOCK_SIZE &&
> + BLOCK_SIZE % cluster_size == 0) {
> + zero_cluster_size = bdi.cluster_size;
> + } else {
> + zero_cluster_size = 0;
> + }
> }
>
> That way we only fetch the cluster size once per device.
>
> When processing a block we do without repeatedly fetching the cluster
> size:
>
> if (zero_cluster_size) {
> ...detect zeroes...
> }
good idea, i will test again for this patch.
>
>> + int i;
>> + int64_t cur_addr;
>> + uint8_t *cur_buf;
>> +
>> + for (i = 0; i < BLOCK_SIZE / cluster_size; i++) {
>> + cur_addr = addr * BDRV_SECTOR_SIZE
>> + + i * cluster_size;
>> + cur_buf = buf + i * cluster_size;
>> +
>> + if (buffer_is_zero(cur_buf, cluster_size)) {
>> + ret = blk_pwrite_zeroes(blk, cur_addr,
>> + cluster_size,
>> + BDRV_REQ_MAY_UNMAP);
>> + } else {
>> + ret = blk_pwrite(blk, cur_addr, cur_buf,
>> + cluster_size, 0);
>
> Indentation is off here.
>
>> + }
>> +
>> + if (ret < 0) {
>> + g_free(buf);
>> + return ret;
>> + }
>> + }
>> + } else {
>> + ret = blk_pwrite(blk, addr * BDRV_SECTOR_SIZE, buf,
>> + nr_sectors * BDRV_SECTOR_SIZE, 0);
>> + }
>> g_free(buf);
>> }
>>
>> --
>> 1.8.3.1
>>
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