2022-11-17 15:22:04

by 李扬韬

[permalink] [raw]
Subject: [PATCH] f2fs: introduce discard_urgent_util sysfs node

Through this node, you can control the background discard
to run more aggressively when reach the utilization rate of
the space.

Signed-off-by: Yangtao Li <[email protected]>
---
Documentation/ABI/testing/sysfs-fs-f2fs | 8 ++++++++
fs/f2fs/f2fs.h | 1 +
fs/f2fs/segment.c | 3 ++-
fs/f2fs/sysfs.c | 9 +++++++++
4 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs
index 24e7cb77f265..202ac1bfc6f2 100644
--- a/Documentation/ABI/testing/sysfs-fs-f2fs
+++ b/Documentation/ABI/testing/sysfs-fs-f2fs
@@ -646,3 +646,11 @@ Date: October 2022
Contact: "Yangtao Li" <[email protected]>
Description: Show the current gc_mode as a string.
This is a read-only entry.
+
+What: /sys/fs/f2fs/<disk>/discard_urgent_util
+Date: November 2022
+Contact: "Yangtao Li" <[email protected]>
+Description: When space utilization exceeds this, do background DISCARD aggressively.
+ Does DISCARD forcibly in a period of given min_discard_issue_time when the number
+ of discards is not 0 and set discard granularity to 1.
+ Default: 80
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index dedac413bf64..fe42ac74491d 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -411,6 +411,7 @@ struct discard_cmd_control {
unsigned int min_discard_issue_time; /* min. interval between discard issue */
unsigned int mid_discard_issue_time; /* mid. interval between discard issue */
unsigned int max_discard_issue_time; /* max. interval between discard issue */
+ unsigned int discard_urgent_util; /* utilization which issue discard proactively */
unsigned int discard_granularity; /* discard granularity */
unsigned int max_ordered_discard; /* maximum discard granularity issued by lba order */
unsigned int undiscard_blks; /* # of undiscard blocks */
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 8b0b76550578..575c24b42df9 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -1069,7 +1069,7 @@ static void __init_discard_policy(struct f2fs_sb_info *sbi,
dpolicy->io_aware = true;
dpolicy->sync = false;
dpolicy->ordered = true;
- if (utilization(sbi) > DEF_DISCARD_URGENT_UTIL) {
+ if (utilization(sbi) > dcc->discard_urgent_util) {
dpolicy->granularity = 1;
if (atomic_read(&dcc->discard_cmd_cnt))
dpolicy->max_interval =
@@ -2085,6 +2085,7 @@ static int create_discard_cmd_control(struct f2fs_sb_info *sbi)
dcc->min_discard_issue_time = DEF_MIN_DISCARD_ISSUE_TIME;
dcc->mid_discard_issue_time = DEF_MID_DISCARD_ISSUE_TIME;
dcc->max_discard_issue_time = DEF_MAX_DISCARD_ISSUE_TIME;
+ dcc->discard_urgent_util = DEF_DISCARD_URGENT_UTIL;
dcc->undiscard_blks = 0;
dcc->next_pos = 0;
dcc->root = RB_ROOT_CACHED;
diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
index 97bf0dbb0974..a7dc726054b9 100644
--- a/fs/f2fs/sysfs.c
+++ b/fs/f2fs/sysfs.c
@@ -493,6 +493,13 @@ static ssize_t __sbi_store(struct f2fs_attr *a,
return count;
}

+ if (!strcmp(a->attr.name, "discard_urgent_util")) {
+ if (t == 0 || t > 100)
+ return -EINVAL;
+ *ui = t;
+ return count;
+ }
+
if (!strcmp(a->attr.name, "migration_granularity")) {
if (t == 0 || t > sbi->segs_per_sec)
return -EINVAL;
@@ -795,6 +802,7 @@ F2FS_RW_ATTR(DCC_INFO, discard_cmd_control, max_discard_request, max_discard_req
F2FS_RW_ATTR(DCC_INFO, discard_cmd_control, min_discard_issue_time, min_discard_issue_time);
F2FS_RW_ATTR(DCC_INFO, discard_cmd_control, mid_discard_issue_time, mid_discard_issue_time);
F2FS_RW_ATTR(DCC_INFO, discard_cmd_control, max_discard_issue_time, max_discard_issue_time);
+F2FS_RW_ATTR(DCC_INFO, discard_cmd_control, discard_urgent_util, discard_urgent_util);
F2FS_RW_ATTR(DCC_INFO, discard_cmd_control, discard_granularity, discard_granularity);
F2FS_RW_ATTR(DCC_INFO, discard_cmd_control, max_ordered_discard, max_ordered_discard);
F2FS_RW_ATTR(RESERVED_BLOCKS, f2fs_sb_info, reserved_blocks, reserved_blocks);
@@ -925,6 +933,7 @@ static struct attribute *f2fs_attrs[] = {
ATTR_LIST(min_discard_issue_time),
ATTR_LIST(mid_discard_issue_time),
ATTR_LIST(max_discard_issue_time),
+ ATTR_LIST(discard_urgent_util),
ATTR_LIST(discard_granularity),
ATTR_LIST(max_ordered_discard),
ATTR_LIST(pending_discard),
--
2.25.1



2022-11-23 16:03:08

by Chao Yu

[permalink] [raw]
Subject: Re: [PATCH] f2fs: introduce discard_urgent_util sysfs node

On 2022/11/17 22:35, Yangtao Li wrote:
> Through this node, you can control the background discard
> to run more aggressively when reach the utilization rate of
> the space.
>
> Signed-off-by: Yangtao Li <[email protected]>
> ---
> Documentation/ABI/testing/sysfs-fs-f2fs | 8 ++++++++
> fs/f2fs/f2fs.h | 1 +
> fs/f2fs/segment.c | 3 ++-
> fs/f2fs/sysfs.c | 9 +++++++++
> 4 files changed, 20 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs
> index 24e7cb77f265..202ac1bfc6f2 100644
> --- a/Documentation/ABI/testing/sysfs-fs-f2fs
> +++ b/Documentation/ABI/testing/sysfs-fs-f2fs
> @@ -646,3 +646,11 @@ Date: October 2022
> Contact: "Yangtao Li" <[email protected]>
> Description: Show the current gc_mode as a string.
> This is a read-only entry.
> +
> +What: /sys/fs/f2fs/<disk>/discard_urgent_util
> +Date: November 2022
> +Contact: "Yangtao Li" <[email protected]>
> +Description: When space utilization exceeds this, do background DISCARD aggressively.
> + Does DISCARD forcibly in a period of given min_discard_issue_time when the number
> + of discards is not 0 and set discard granularity to 1.
> + Default: 80
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index dedac413bf64..fe42ac74491d 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -411,6 +411,7 @@ struct discard_cmd_control {
> unsigned int min_discard_issue_time; /* min. interval between discard issue */
> unsigned int mid_discard_issue_time; /* mid. interval between discard issue */
> unsigned int max_discard_issue_time; /* max. interval between discard issue */
> + unsigned int discard_urgent_util; /* utilization which issue discard proactively */
> unsigned int discard_granularity; /* discard granularity */
> unsigned int max_ordered_discard; /* maximum discard granularity issued by lba order */
> unsigned int undiscard_blks; /* # of undiscard blocks */
> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
> index 8b0b76550578..575c24b42df9 100644
> --- a/fs/f2fs/segment.c
> +++ b/fs/f2fs/segment.c
> @@ -1069,7 +1069,7 @@ static void __init_discard_policy(struct f2fs_sb_info *sbi,
> dpolicy->io_aware = true;
> dpolicy->sync = false;
> dpolicy->ordered = true;
> - if (utilization(sbi) > DEF_DISCARD_URGENT_UTIL) {
> + if (utilization(sbi) > dcc->discard_urgent_util) {
> dpolicy->granularity = 1;
> if (atomic_read(&dcc->discard_cmd_cnt))
> dpolicy->max_interval =
> @@ -2085,6 +2085,7 @@ static int create_discard_cmd_control(struct f2fs_sb_info *sbi)
> dcc->min_discard_issue_time = DEF_MIN_DISCARD_ISSUE_TIME;
> dcc->mid_discard_issue_time = DEF_MID_DISCARD_ISSUE_TIME;
> dcc->max_discard_issue_time = DEF_MAX_DISCARD_ISSUE_TIME;
> + dcc->discard_urgent_util = DEF_DISCARD_URGENT_UTIL;
> dcc->undiscard_blks = 0;
> dcc->next_pos = 0;
> dcc->root = RB_ROOT_CACHED;
> diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
> index 97bf0dbb0974..a7dc726054b9 100644
> --- a/fs/f2fs/sysfs.c
> +++ b/fs/f2fs/sysfs.c
> @@ -493,6 +493,13 @@ static ssize_t __sbi_store(struct f2fs_attr *a,
> return count;
> }
>
> + if (!strcmp(a->attr.name, "discard_urgent_util")) {
> + if (t == 0 || t > 100)

0 is allowed?

Thanks,

> + return -EINVAL;
> + *ui = t;
> + return count;
> + }
> +
> if (!strcmp(a->attr.name, "migration_granularity")) {
> if (t == 0 || t > sbi->segs_per_sec)
> return -EINVAL;
> @@ -795,6 +802,7 @@ F2FS_RW_ATTR(DCC_INFO, discard_cmd_control, max_discard_request, max_discard_req
> F2FS_RW_ATTR(DCC_INFO, discard_cmd_control, min_discard_issue_time, min_discard_issue_time);
> F2FS_RW_ATTR(DCC_INFO, discard_cmd_control, mid_discard_issue_time, mid_discard_issue_time);
> F2FS_RW_ATTR(DCC_INFO, discard_cmd_control, max_discard_issue_time, max_discard_issue_time);
> +F2FS_RW_ATTR(DCC_INFO, discard_cmd_control, discard_urgent_util, discard_urgent_util);
> F2FS_RW_ATTR(DCC_INFO, discard_cmd_control, discard_granularity, discard_granularity);
> F2FS_RW_ATTR(DCC_INFO, discard_cmd_control, max_ordered_discard, max_ordered_discard);
> F2FS_RW_ATTR(RESERVED_BLOCKS, f2fs_sb_info, reserved_blocks, reserved_blocks);
> @@ -925,6 +933,7 @@ static struct attribute *f2fs_attrs[] = {
> ATTR_LIST(min_discard_issue_time),
> ATTR_LIST(mid_discard_issue_time),
> ATTR_LIST(max_discard_issue_time),
> + ATTR_LIST(discard_urgent_util),
> ATTR_LIST(discard_granularity),
> ATTR_LIST(max_ordered_discard),
> ATTR_LIST(pending_discard),