lkml.org 
[lkml]   [2022]   [Feb]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [f2fs-dev] [PATCH v2] f2fs: add a way to limit roll forward recovery time
From
On 2022/2/4 14:16, Jaegeuk Kim wrote:
> On 02/04, Chao Yu wrote:
>> On 2022/2/4 1:42, Jaegeuk Kim wrote:
>>> On 02/03, Chao Yu wrote:
>>>> On 2022/2/3 8:34, Jaegeuk Kim wrote:
>>>>> This adds a sysfs entry to call checkpoint during fsync() in order to avoid
>>>>> long elapsed time to run roll-forward recovery when booting the device.
>>>>> Default value doesn't enforce the limitation which is same as before.
>>>>>
>>>>> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
>>>>> ---
>>>>> v2 from v1:
>>>>> - make the default w/o enforcement
>>>>>
>>>>> Documentation/ABI/testing/sysfs-fs-f2fs | 6 ++++++
>>>>> fs/f2fs/checkpoint.c | 1 +
>>>>> fs/f2fs/f2fs.h | 3 +++
>>>>> fs/f2fs/node.c | 2 ++
>>>>> fs/f2fs/node.h | 3 +++
>>>>> fs/f2fs/recovery.c | 4 ++++
>>>>> fs/f2fs/sysfs.c | 2 ++
>>>>> 7 files changed, 21 insertions(+)
>>>>>
>>>>> diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs
>>>>> index 87d3884c90ea..ce8103f522cb 100644
>>>>> --- a/Documentation/ABI/testing/sysfs-fs-f2fs
>>>>> +++ b/Documentation/ABI/testing/sysfs-fs-f2fs
>>>>> @@ -567,3 +567,9 @@ Contact: "Daeho Jeong" <daehojeong@google.com>
>>>>> Description: You can set the trial count limit for GC urgent high mode with this value.
>>>>> If GC thread gets to the limit, the mode will turn back to GC normal mode.
>>>>> By default, the value is zero, which means there is no limit like before.
>>>>> +
>>>>> +What: /sys/fs/f2fs/<disk>/max_roll_forward_node_blocks
>>>>> +Date: January 2022
>>>>> +Contact: "Jaegeuk Kim" <jaegeuk@kernel.org>
>>>>> +Description: Controls max # of node block writes to be used for roll forward
>>>>> + recovery. This can limit the roll forward recovery time.
>>>>> diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
>>>>> index deeda95688f0..57a2d9164bee 100644
>>>>> --- a/fs/f2fs/checkpoint.c
>>>>> +++ b/fs/f2fs/checkpoint.c
>>>>> @@ -1543,6 +1543,7 @@ static int do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
>>>>> /* update user_block_counts */
>>>>> sbi->last_valid_block_count = sbi->total_valid_block_count;
>>>>> percpu_counter_set(&sbi->alloc_valid_block_count, 0);
>>>>> + percpu_counter_set(&sbi->rf_node_block_count, 0);

Should be initialized before use?

Thanks,

>>>>> /* Here, we have one bio having CP pack except cp pack 2 page */
>>>>> f2fs_sync_meta_pages(sbi, META, LONG_MAX, FS_CP_META_IO);
>>>>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
>>>>> index 63c90416364b..6ddb98ff0b7c 100644
>>>>> --- a/fs/f2fs/f2fs.h
>>>>> +++ b/fs/f2fs/f2fs.h
>>>>> @@ -913,6 +913,7 @@ struct f2fs_nm_info {
>>>>> nid_t max_nid; /* maximum possible node ids */
>>>>> nid_t available_nids; /* # of available node ids */
>>>>> nid_t next_scan_nid; /* the next nid to be scanned */
>>>>> + nid_t max_rf_node_blocks; /* max # of nodes for recovery */
>>>>> unsigned int ram_thresh; /* control the memory footprint */
>>>>> unsigned int ra_nid_pages; /* # of nid pages to be readaheaded */
>>>>> unsigned int dirty_nats_ratio; /* control dirty nats ratio threshold */
>>>>> @@ -1684,6 +1685,8 @@ struct f2fs_sb_info {
>>>>> atomic_t nr_pages[NR_COUNT_TYPE];
>>>>> /* # of allocated blocks */
>>>>> struct percpu_counter alloc_valid_block_count;
>>>>> + /* # of node block writes as roll forward recovery */
>>>>> + struct percpu_counter rf_node_block_count;
>>>>> /* writeback control */
>>>>> atomic_t wb_sync_req[META]; /* count # of WB_SYNC threads */
>>>>> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
>>>>> index 93512f8859d5..0d9883457579 100644
>>>>> --- a/fs/f2fs/node.c
>>>>> +++ b/fs/f2fs/node.c
>>>>> @@ -1782,6 +1782,7 @@ int f2fs_fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode,
>>>>> if (!atomic || page == last_page) {
>>>>> set_fsync_mark(page, 1);
>>>>> + percpu_counter_inc(&sbi->rf_node_block_count);
>>>>
>>>> if (NM_I(sbi)->max_rf_node_blocks)
>>>> percpu_counter_inc(&sbi->rf_node_block_count);
>>>
>>> I think we can just count this and adjust right away once sysfs is changed.
>>
>> Since this long recovery latency issue is a corner case, I guess we can avoid this
>> to save cpu time...
>
> I think we can show this in debugfs, as it won't give huge overhead.
>
>>
>> BTW, shouldn't we account all warn dnode blocks? as we will traverse all blocks there
>> in warn node list.
>
> I thought we don't need to track the whole bunch of chains, but would be enough
> to record # of fsync calls roughly.
>
>>
>> Thanks,
>>
>>>
>>>>
>>>> Thanks,
>>>>
>>>>> if (IS_INODE(page)) {
>>>>> if (is_inode_flag_set(inode,
>>>>> FI_DIRTY_INODE))
>>>>> @@ -3218,6 +3219,7 @@ static int init_node_manager(struct f2fs_sb_info *sbi)
>>>>> nm_i->ram_thresh = DEF_RAM_THRESHOLD;
>>>>> nm_i->ra_nid_pages = DEF_RA_NID_PAGES;
>>>>> nm_i->dirty_nats_ratio = DEF_DIRTY_NAT_RATIO_THRESHOLD;
>>>>> + nm_i->max_rf_node_blocks = DEF_RF_NODE_BLOCKS;
>>>>> INIT_RADIX_TREE(&nm_i->free_nid_root, GFP_ATOMIC);
>>>>> INIT_LIST_HEAD(&nm_i->free_nid_list);
>>>>> diff --git a/fs/f2fs/node.h b/fs/f2fs/node.h
>>>>> index 18b98cf0465b..4c1d34bfea78 100644
>>>>> --- a/fs/f2fs/node.h
>>>>> +++ b/fs/f2fs/node.h
>>>>> @@ -31,6 +31,9 @@
>>>>> /* control total # of nats */
>>>>> #define DEF_NAT_CACHE_THRESHOLD 100000
>>>>> +/* control total # of node writes used for roll-fowrad recovery */
>>>>> +#define DEF_RF_NODE_BLOCKS 0
>>>>> +
>>>>> /* vector size for gang look-up from nat cache that consists of radix tree */
>>>>> #define NATVEC_SIZE 64
>>>>> #define SETVEC_SIZE 32
>>>>> diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c
>>>>> index 10d152cfa58d..1c8041fd854e 100644
>>>>> --- a/fs/f2fs/recovery.c
>>>>> +++ b/fs/f2fs/recovery.c
>>>>> @@ -53,9 +53,13 @@ extern struct kmem_cache *f2fs_cf_name_slab;
>>>>> bool f2fs_space_for_roll_forward(struct f2fs_sb_info *sbi)
>>>>> {
>>>>> s64 nalloc = percpu_counter_sum_positive(&sbi->alloc_valid_block_count);
>>>>> + u32 rf_node = percpu_counter_sum_positive(&sbi->rf_node_block_count);
>>>>> if (sbi->last_valid_block_count + nalloc > sbi->user_block_count)
>>>>> return false;
>>>>> + if (NM_I(sbi)->max_rf_node_blocks &&
>>>>> + rf_node >= NM_I(sbi)->max_rf_node_blocks)
>>>>> + return false;
>>>>> return true;
>>>>> }
>>>>> diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
>>>>> index 281bc0133ee6..47efcf233afd 100644
>>>>> --- a/fs/f2fs/sysfs.c
>>>>> +++ b/fs/f2fs/sysfs.c
>>>>> @@ -732,6 +732,7 @@ F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_ssr_sections, min_ssr_sections);
>>>>> F2FS_RW_ATTR(NM_INFO, f2fs_nm_info, ram_thresh, ram_thresh);
>>>>> F2FS_RW_ATTR(NM_INFO, f2fs_nm_info, ra_nid_pages, ra_nid_pages);
>>>>> F2FS_RW_ATTR(NM_INFO, f2fs_nm_info, dirty_nats_ratio, dirty_nats_ratio);
>>>>> +F2FS_RW_ATTR(NM_INFO, f2fs_nm_info, max_roll_forward_node_blocks, max_rf_node_blocks);
>>>>> F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, max_victim_search, max_victim_search);
>>>>> F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, migration_granularity, migration_granularity);
>>>>> F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, dir_level, dir_level);
>>>>> @@ -855,6 +856,7 @@ static struct attribute *f2fs_attrs[] = {
>>>>> ATTR_LIST(ram_thresh),
>>>>> ATTR_LIST(ra_nid_pages),
>>>>> ATTR_LIST(dirty_nats_ratio),
>>>>> + ATTR_LIST(max_roll_forward_node_blocks),
>>>>> ATTR_LIST(cp_interval),
>>>>> ATTR_LIST(idle_interval),
>>>>> ATTR_LIST(discard_idle_interval),

\
 
 \ /
  Last update: 2022-02-04 13:03    [W:0.063 / U:0.288 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site