Re: [f2fs-dev] [PATCH v5 1/2] f2fs: introduce checkpoint=merge mount option
Yep~
2021년 1월 22일 (금) 오전 10:46, Jaegeuk Kim 님이 작성:
>
> On 01/21, Daeho Jeong wrote:
> > From: Daeho Jeong
> >
> > We've added a new mount option "checkpoint=merge", which creates a
> > kernel daemon and makes it to merge concurrent checkpoint requests as
> > much as possible to eliminate redundant checkpoint issues. Plus, we
> > can eliminate the sluggish issue caused by slow checkpoint operation
> > when the checkpoint is done in a process context in a cgroup having
> > low i/o budget and cpu shares. To make this do better, we set the
> > default i/o priority of the kernel daemon to "3", to give one higher
> > priority than other kernel threads. The below verification result
> > explains this.
> > The basic idea has come from https://opensource.samsung.com.
> >
> > [Verification]
> > Android Pixel Device(ARM64, 7GB RAM, 256GB UFS)
> > Create two I/O cgroups (fg w/ weight 100, bg w/ wight 20)
> > Set "strict_guarantees" to "1" in BFQ tunables
> >
> > In "fg" cgroup,
> > - thread A => trigger 1000 checkpoint operations
> > "for i in `seq 1 1000`; do touch test_dir1/file; fsync test_dir1;
> >done"
> > - thread B => gererating async. I/O
> > "fio --rw=write --numjobs=1 --bs=128k --runtime=3600 --time_based=1
> >--filename=test_img --name=test"
> >
> > In "bg" cgroup,
> > - thread C => trigger repeated checkpoint operations
> > "echo $$ > /dev/blkio/bg/tasks; while true; do touch test_dir2/file;
> >fsync test_dir2; done"
> >
> > We've measured thread A's execution time.
> >
> > [ w/o patch ]
> > Elapsed Time: Avg. 68 seconds
> > [ w/ patch ]
> > Elapsed Time: Avg. 48 seconds
> >
> > Signed-off-by: Daeho Jeong
> > Signed-off-by: Sungjong Seo
> > ---
> > v2:
> > - inlined ckpt_req_control into f2fs_sb_info and collected stastics
> > of checkpoint merge operations
> > v3:
> > - fixed some minor errors and cleaned up f2fs_sync_fs()
> > v4:
> > - added an explanation to raise the default i/o priority of the
> > checkpoint daemon
> > ---
> > Documentation/filesystems/f2fs.rst | 10 ++
> > fs/f2fs/checkpoint.c | 177 +
> > fs/f2fs/debug.c| 12 ++
> > fs/f2fs/f2fs.h | 27 +
> > fs/f2fs/super.c| 55 +++--
> > 5 files changed, 273 insertions(+), 8 deletions(-)
> >
> > diff --git a/Documentation/filesystems/f2fs.rst
> > b/Documentation/filesystems/f2fs.rst
> > index dae15c96e659..9624a0be0364 100644
> > --- a/Documentation/filesystems/f2fs.rst
> > +++ b/Documentation/filesystems/f2fs.rst
> > @@ -247,6 +247,16 @@ checkpoint=%s[:%u[%]] Set to "disable" to turn off
> > checkpointing. Set to "enabl
> >hide up to all remaining free space. The actual
> > space that
> >would be unusable can be viewed at
> > /sys/fs/f2fs//unusable
> >This space is reclaimed once checkpoint=enable.
> > + Here is another option "merge", which creates a
> > kernel daemon
> > + and makes it to merge concurrent checkpoint requests
> > as much
> > + as possible to eliminate redundant checkpoint
> > issues. Plus,
> > + we can eliminate the sluggish issue caused by slow
> > checkpoint
> > + operation when the checkpoint is done in a process
> > context in
> > + a cgroup having low i/o budget and cpu shares. To
> > make this
> > + do better, we set the default i/o priority of the
> > kernel daemon
> > + to "3", to give one higher priority than other
> > kernel threads.
> > + This is the same way to give a I/O priority to the
> > jbd2
> > + journaling thread of ext4 filesystem.
> > compress_algorithm=%s Control compress algorithm, currently f2fs
> > supports "lzo",
> >"lz4", "zstd" and "lzo-rle" algorithm.
> > compress_log_size=%u Support configuring compress cluster size, the size
> > will
> > diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
> > index 897edb7c951a..ef6ad3d1957d 100644
> > --- a/fs/f2fs/checkpoint.c
> > +++ b/fs/f2fs/checkpoint.c
> > @@ -13,6 +13,7 @@
> > #include
> > #include
> > #include
> > +#include
> >
> > #include "f2fs.h"
> > #include "node.h"
> > @@ -20,6 +21,8 @@
> > #include "trace.h"
> > #include
> >
> > +#define DEFAULT_CHECKPOINT_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
> > +
> > static struct kmem_cache *ino_entry_slab;
> > struct kmem_cache *f2fs_inode_entry_slab;
> >
> > @@ -1707,3 +1710,177 @@ void f2fs_destroy_checkpoint_caches(void)
> > kmem_cache_destroy(ino_entry_slab);
> > kmem_cache_destroy(f2fs_inode_entry_slab);
> > }
> > +
> > +static int __write_checkpoint_sync(struct f2fs_sb_info *sbi)
> > +{
> > + struct cp_control cpc = { .reason = CP_SYNC, };
> > + int err;
> > +
> > +
Re: [f2fs-dev] [PATCH v5 1/2] f2fs: introduce checkpoint=merge mount option
On 01/21, Daeho Jeong wrote:
> From: Daeho Jeong
>
> We've added a new mount option "checkpoint=merge", which creates a
> kernel daemon and makes it to merge concurrent checkpoint requests as
> much as possible to eliminate redundant checkpoint issues. Plus, we
> can eliminate the sluggish issue caused by slow checkpoint operation
> when the checkpoint is done in a process context in a cgroup having
> low i/o budget and cpu shares. To make this do better, we set the
> default i/o priority of the kernel daemon to "3", to give one higher
> priority than other kernel threads. The below verification result
> explains this.
> The basic idea has come from https://opensource.samsung.com.
>
> [Verification]
> Android Pixel Device(ARM64, 7GB RAM, 256GB UFS)
> Create two I/O cgroups (fg w/ weight 100, bg w/ wight 20)
> Set "strict_guarantees" to "1" in BFQ tunables
>
> In "fg" cgroup,
> - thread A => trigger 1000 checkpoint operations
> "for i in `seq 1 1000`; do touch test_dir1/file; fsync test_dir1;
>done"
> - thread B => gererating async. I/O
> "fio --rw=write --numjobs=1 --bs=128k --runtime=3600 --time_based=1
>--filename=test_img --name=test"
>
> In "bg" cgroup,
> - thread C => trigger repeated checkpoint operations
> "echo $$ > /dev/blkio/bg/tasks; while true; do touch test_dir2/file;
>fsync test_dir2; done"
>
> We've measured thread A's execution time.
>
> [ w/o patch ]
> Elapsed Time: Avg. 68 seconds
> [ w/ patch ]
> Elapsed Time: Avg. 48 seconds
>
> Signed-off-by: Daeho Jeong
> Signed-off-by: Sungjong Seo
> ---
> v2:
> - inlined ckpt_req_control into f2fs_sb_info and collected stastics
> of checkpoint merge operations
> v3:
> - fixed some minor errors and cleaned up f2fs_sync_fs()
> v4:
> - added an explanation to raise the default i/o priority of the
> checkpoint daemon
> ---
> Documentation/filesystems/f2fs.rst | 10 ++
> fs/f2fs/checkpoint.c | 177 +
> fs/f2fs/debug.c| 12 ++
> fs/f2fs/f2fs.h | 27 +
> fs/f2fs/super.c| 55 +++--
> 5 files changed, 273 insertions(+), 8 deletions(-)
>
> diff --git a/Documentation/filesystems/f2fs.rst
> b/Documentation/filesystems/f2fs.rst
> index dae15c96e659..9624a0be0364 100644
> --- a/Documentation/filesystems/f2fs.rst
> +++ b/Documentation/filesystems/f2fs.rst
> @@ -247,6 +247,16 @@ checkpoint=%s[:%u[%]] Set to "disable" to turn off
> checkpointing. Set to "enabl
>hide up to all remaining free space. The actual space
> that
>would be unusable can be viewed at
> /sys/fs/f2fs//unusable
>This space is reclaimed once checkpoint=enable.
> + Here is another option "merge", which creates a kernel
> daemon
> + and makes it to merge concurrent checkpoint requests
> as much
> + as possible to eliminate redundant checkpoint issues.
> Plus,
> + we can eliminate the sluggish issue caused by slow
> checkpoint
> + operation when the checkpoint is done in a process
> context in
> + a cgroup having low i/o budget and cpu shares. To make
> this
> + do better, we set the default i/o priority of the
> kernel daemon
> + to "3", to give one higher priority than other kernel
> threads.
> + This is the same way to give a I/O priority to the jbd2
> + journaling thread of ext4 filesystem.
> compress_algorithm=%s Control compress algorithm, currently f2fs
> supports "lzo",
>"lz4", "zstd" and "lzo-rle" algorithm.
> compress_log_size=%u Support configuring compress cluster size, the size
> will
> diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
> index 897edb7c951a..ef6ad3d1957d 100644
> --- a/fs/f2fs/checkpoint.c
> +++ b/fs/f2fs/checkpoint.c
> @@ -13,6 +13,7 @@
> #include
> #include
> #include
> +#include
>
> #include "f2fs.h"
> #include "node.h"
> @@ -20,6 +21,8 @@
> #include "trace.h"
> #include
>
> +#define DEFAULT_CHECKPOINT_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
> +
> static struct kmem_cache *ino_entry_slab;
> struct kmem_cache *f2fs_inode_entry_slab;
>
> @@ -1707,3 +1710,177 @@ void f2fs_destroy_checkpoint_caches(void)
> kmem_cache_destroy(ino_entry_slab);
> kmem_cache_destroy(f2fs_inode_entry_slab);
> }
> +
> +static int __write_checkpoint_sync(struct f2fs_sb_info *sbi)
> +{
> + struct cp_control cpc = { .reason = CP_SYNC, };
> + int err;
> +
> + down_write(>gc_lock);
> + err = f2fs_write_checkpoint(sbi, );
> + up_write(>gc_lock);
> +
> + return err;
> +}
> +
> +static void __checkpoint_and_complete_reqs(struct f2fs_sb_info *sbi)
> +{
> + struct ckpt_req_control *cprc = >cprc_info;
> + struct ckpt_req *req, *next;
> + struct
Re: [f2fs-dev] [PATCH v5 1/2] f2fs: introduce checkpoint=merge mount option
Got it~! :) 2021년 1월 22일 (금) 오전 9:55, Chao Yu 님이 작성: > > If there is no update in v5, it will be better to include my Reviewed-by > tag, please note that. :) > > Thanks, > > On 2021/1/21 21:45, Daeho Jeong wrote: > > From: Daeho Jeong > > > > We've added a new mount option "checkpoint=merge", which creates a > > kernel daemon and makes it to merge concurrent checkpoint requests as > > much as possible to eliminate redundant checkpoint issues. Plus, we > > can eliminate the sluggish issue caused by slow checkpoint operation > > when the checkpoint is done in a process context in a cgroup having > > low i/o budget and cpu shares. To make this do better, we set the > > default i/o priority of the kernel daemon to "3", to give one higher > > priority than other kernel threads. The below verification result > > explains this. > > The basic idea has come fromhttps://opensource.samsung.com. > > > > [Verification] > > Android Pixel Device(ARM64, 7GB RAM, 256GB UFS) > > Create two I/O cgroups (fg w/ weight 100, bg w/ wight 20) > > Set "strict_guarantees" to "1" in BFQ tunables > > > > In "fg" cgroup, > > - thread A => trigger 1000 checkpoint operations > >"for i in `seq 1 1000`; do touch test_dir1/file; fsync test_dir1; > > done" > > - thread B => gererating async. I/O > >"fio --rw=write --numjobs=1 --bs=128k --runtime=3600 --time_based=1 > > --filename=test_img --name=test" > > > > In "bg" cgroup, > > - thread C => trigger repeated checkpoint operations > >"echo $$ > /dev/blkio/bg/tasks; while true; do touch test_dir2/file; > > fsync test_dir2; done" > > > > We've measured thread A's execution time. > > > > [ w/o patch ] > > Elapsed Time: Avg. 68 seconds > > [ w/ patch ] > > Elapsed Time: Avg. 48 seconds > > > > Signed-off-by: Daeho Jeong > > Signed-off-by: Sungjong Seo
Re: [f2fs-dev] [PATCH v5 1/2] f2fs: introduce checkpoint=merge mount option
If there is no update in v5, it will be better to include my Reviewed-by tag, please note that. :) Thanks, On 2021/1/21 21:45, Daeho Jeong wrote: From: Daeho Jeong We've added a new mount option "checkpoint=merge", which creates a kernel daemon and makes it to merge concurrent checkpoint requests as much as possible to eliminate redundant checkpoint issues. Plus, we can eliminate the sluggish issue caused by slow checkpoint operation when the checkpoint is done in a process context in a cgroup having low i/o budget and cpu shares. To make this do better, we set the default i/o priority of the kernel daemon to "3", to give one higher priority than other kernel threads. The below verification result explains this. The basic idea has come fromhttps://opensource.samsung.com. [Verification] Android Pixel Device(ARM64, 7GB RAM, 256GB UFS) Create two I/O cgroups (fg w/ weight 100, bg w/ wight 20) Set "strict_guarantees" to "1" in BFQ tunables In "fg" cgroup, - thread A => trigger 1000 checkpoint operations "for i in `seq 1 1000`; do touch test_dir1/file; fsync test_dir1; done" - thread B => gererating async. I/O "fio --rw=write --numjobs=1 --bs=128k --runtime=3600 --time_based=1 --filename=test_img --name=test" In "bg" cgroup, - thread C => trigger repeated checkpoint operations "echo $$ > /dev/blkio/bg/tasks; while true; do touch test_dir2/file; fsync test_dir2; done" We've measured thread A's execution time. [ w/o patch ] Elapsed Time: Avg. 68 seconds [ w/ patch ] Elapsed Time: Avg. 48 seconds Signed-off-by: Daeho Jeong Signed-off-by: Sungjong Seo
