2020-09-10 20:58:59

by Christoph Hellwig

Subject: [PATCH 05/12] md: update the optimal I/O size on reshape

The raid5 and raid10 drivers currently update the read-ahead size,
but not the optimal I/O size on reshape. To prepare for deriving the
read-ahead size from the optimal I/O size make sure it is updated
as well.

Signed-off-by: Christoph Hellwig <[email protected]>
---
drivers/md/raid10.c | 22 ++++++++++++++--------
drivers/md/raid5.c | 10 ++++++++--
2 files changed, 22 insertions(+), 10 deletions(-)

diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index e8fa327339171c..9956a04ac13bd6 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -3703,10 +3703,20 @@ static struct r10conf *setup_conf(struct mddev *mddev)
return ERR_PTR(err);
}

+static void raid10_set_io_opt(struct r10conf *conf)
+{
+ int raid_disks = conf->geo.raid_disks;
+
+ if (!(conf->geo.raid_disks % conf->geo.near_copies))
+ raid_disks /= conf->geo.near_copies;
+ blk_queue_io_opt(conf->mddev->queue, (conf->mddev->chunk_sectors << 9) *
+ raid_disks);
+}
+
static int raid10_run(struct mddev *mddev)
{
struct r10conf *conf;
- int i, disk_idx, chunk_size;
+ int i, disk_idx;
struct raid10_info *disk;
struct md_rdev *rdev;
sector_t size;
@@ -3742,18 +3752,13 @@ static int raid10_run(struct mddev *mddev)
mddev->thread = conf->thread;
conf->thread = NULL;

- chunk_size = mddev->chunk_sectors << 9;
if (mddev->queue) {
blk_queue_max_discard_sectors(mddev->queue,
mddev->chunk_sectors);
blk_queue_max_write_same_sectors(mddev->queue, 0);
blk_queue_max_write_zeroes_sectors(mddev->queue, 0);
- blk_queue_io_min(mddev->queue, chunk_size);
- if (conf->geo.raid_disks % conf->geo.near_copies)
- blk_queue_io_opt(mddev->queue, chunk_size * conf->geo.raid_disks);
- else
- blk_queue_io_opt(mddev->queue, chunk_size *
- (conf->geo.raid_disks / conf->geo.near_copies));
+ blk_queue_io_min(mddev->queue, mddev->chunk_sectors << 9);
+ raid10_set_io_opt(conf);
}

rdev_for_each(rdev, mddev) {
@@ -4727,6 +4732,7 @@ static void end_reshape(struct r10conf *conf)
stripe /= conf->geo.near_copies;
if (conf->mddev->queue->backing_dev_info->ra_pages < 2 * stripe)
conf->mddev->queue->backing_dev_info->ra_pages = 2 * stripe;
+ raid10_set_io_opt(conf);
}
conf->fullsync = 0;
}
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 225380efd1e24f..9a7d1250894ef1 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -7232,6 +7232,12 @@ static int only_parity(int raid_disk, int algo, int raid_disks, int max_degraded
return 0;
}

+static void raid5_set_io_opt(struct r5conf *conf)
+{
+ blk_queue_io_opt(conf->mddev->queue, (conf->chunk_sectors << 9) *
+ (conf->raid_disks - conf->max_degraded));
+}
+
static int raid5_run(struct mddev *mddev)
{
struct r5conf *conf;
@@ -7521,8 +7527,7 @@ static int raid5_run(struct mddev *mddev)

chunk_size = mddev->chunk_sectors << 9;
blk_queue_io_min(mddev->queue, chunk_size);
- blk_queue_io_opt(mddev->queue, chunk_size *
- (conf->raid_disks - conf->max_degraded));
+ raid5_set_io_opt(conf);
mddev->queue->limits.raid_partial_stripes_expensive = 1;
/*
* We can only discard a whole stripe. It doesn't make sense to
@@ -8115,6 +8120,7 @@ static void end_reshape(struct r5conf *conf)
/ PAGE_SIZE);
if (conf->mddev->queue->backing_dev_info->ra_pages < 2 * stripe)
conf->mddev->queue->backing_dev_info->ra_pages = 2 * stripe;
+ raid5_set_io_opt(conf);
}
}
}
--
2.28.0

2020-09-12 06:18:47

by Song Liu

Subject: Re: [PATCH 05/12] md: update the optimal I/O size on reshape

On Thu, Sep 10, 2020 at 7:48 AM Christoph Hellwig <[email protected]> wrote:
>
> The raid5 and raid10 drivers currently update the read-ahead size,
> but not the optimal I/O size on reshape. To prepare for deriving the
> read-ahead size from the optimal I/O size make sure it is updated
> as well.
>
> Signed-off-by: Christoph Hellwig <[email protected]>

Acked-by: Song Liu <[email protected]>