Commit Graph

28 Commits

Author SHA1 Message Date
Jaegeuk Kim bba681cbb2 f2fs: introduce a batched trim
This patch introduces a batched trimming feature, which submits split discard
commands.

This is to avoid long latency due to huge trim commands.
If fstrim was triggered ranging from 0 to the end of device, we should lock
all the checkpoint-related mutexes, resulting in very long latency.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-02-11 17:04:44 -08:00
Jaegeuk Kim 2d834bf9ac f2fs: support norecovery mount option
This patch adds a mount option, norecovery, which is mostly same as
disable_roll_forward. The only difference is that norecovery should be activated
with read-only mount option.

This can be used when user wants to check whether f2fs is mountable or not
without any recovery process. (e.g., xfstests/200)

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-02-11 17:04:40 -08:00
Jaegeuk Kim d5053a34a9 f2fs: introduce -o fastboot for reducing booting time only
If a system wants to reduce the booting time as a top priority, now we can
use a mount option, -o fastboot.
With this option, f2fs conducts a little bit slow write_checkpoint, but
it can avoid the node page reads during the next mount time.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-04 17:34:15 -08:00
Chao Yu d37a868ffc f2fs: update f2fs documentation for inline dir support
This patch adds descriptions for the inline dir support in f2fs document.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-03 16:07:32 -08:00
Jaegeuk Kim 9b5f136fd4 f2fs: change the ipu_policy option to enable combinations
This patch changes the ipu_policy setting to use any combination of orthogonal policies.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-23 11:10:24 -07:00
Jaegeuk Kim c1ce1b02bb f2fs: give an option to enable in-place-updates during fsync to users
If user wrote F2FS_IPU_FSYNC:4 in /sys/fs/f2fs/ipu_policy, f2fs_sync_file
only starts to try in-place-updates.
And, if the number of dirty pages is over /sys/fs/f2fs/min_fsync_blocks, it
keeps out-of-order manner. Otherwise, it triggers in-place-updates.

This may be used by storage showing very high random write performance.

For example, it can be used when,

Seq. writes (Data) + wait + Seq. writes (Node)

is pretty much slower than,

Rand. writes (Data)

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-16 04:10:44 -07:00
Jaegeuk Kim 0f7b2abd18 f2fs: add nobarrier mount option
This patch adds a mount option, nobarrier, in f2fs.
The assumption in here is that file system keeps the IO ordering, but
doesn't care about cache flushes inside the storages.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-07-29 05:27:48 -07:00
Chao Yu bfec07d0f8 f2fs: avoid overflow when large directory feathure is enabled
When large directory feathure is enable, We have one case which could cause
overflow in dir_buckets() as following:
special case: level + dir_level >= 32 and level < MAX_DIR_HASH_DEPTH / 2.

Here we define MAX_DIR_BUCKETS to limit the return value when the condition
could trigger potential overflow.

Changes from V1
 o modify description of calculation in f2fs.txt suggested by Changman Lee.

Suggested-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-06-04 13:34:30 +09:00
Jaegeuk Kim 6b4afdd794 f2fs: introduce f2fs_issue_flush to avoid redundant flush issue
Some storage devices show relatively high latencies to complete cache_flush
commands, even though their normal IO speed is prettry much high. In such
the case, it needs to merge cache_flush commands as much as possible to avoid
issuing them redundantly.
So, this patch introduces a mount option, "-o flush_merge", to mitigate such
the overhead.

If this option is enabled by user, F2FS merges the cache_flush commands and then
issues just one cache_flush on behalf of them. Once the single command is
finished, F2FS sends a completion signal to all the pending threads.

Note that, this option can be used under a workload consisting of very intensive
concurrent fsync calls, while the storage handles cache_flush commands slowly.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-04-07 09:50:58 +09:00
Jaegeuk Kim 58c410351e f2fs: change reclaim rate in percentage
It is more reasonable to determine the reclaiming rate of prefree segments
according to the volume size, which is set to 5% by default.
For example, if the volume is 128GB, the prefree segments are reclaimed
when the number reaches to 6.4GB.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-03-20 22:10:10 +09:00
Jaegeuk Kim cdfc41c134 f2fs: throttle the memory footprint with a sysfs entry
This patch introduces ram_thresh, a sysfs entry, which controls the memory
footprint used by the free nid list and the nat cache.

Previously, the free nid list was controlled by MAX_FREE_NIDS, while the nat
cache was managed by NM_WOUT_THRESHOLD.
However, this approach cannot be applied dynamically according to the system.

So, this patch adds ram_thresh that users can specify the threshold, which is
in order of 1 / 1024.
For example, if the total ram size is 4GB and the value is set to 10 by default,
f2fs tries to control the number of free nids and nat caches not to consume over
10 * (4GB / 1024) = 10MB.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-03-20 22:10:09 +09:00
Jaegeuk Kim ab9fa662e4 f2fs: add an sysfs entry to control the directory level
This patch adds an sysfs entry to control dir_level used by the large directory.

The description of this entry is:

 dir_level                    This parameter controls the directory level to
			      support large directory. If a directory has a
			      number of files, it can reduce the file lookup
			      latency by increasing this dir_level value.
			      Otherwise, it needs to decrease this value to
			      reduce the space overhead. The default value is 0.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-02-27 20:31:15 +09:00
Jaegeuk Kim 3843154598 f2fs: introduce large directory support
This patch introduces an i_dir_level field to support large directory.

Previously, f2fs maintains multi-level hash tables to find a dentry quickly
from a bunch of chiild dentries in a directory, and the hash tables consist of
the following tree structure as below.

In Documentation/filesystems/f2fs.txt,

----------------------
A : bucket
B : block
N : MAX_DIR_HASH_DEPTH
----------------------

level #0   | A(2B)
           |
level #1   | A(2B) - A(2B)
           |
level #2   | A(2B) - A(2B) - A(2B) - A(2B)
     .     |   .       .       .       .
level #N/2 | A(2B) - A(2B) - A(2B) - A(2B) - A(2B) - ... - A(2B)
     .     |   .       .       .       .
level #N   | A(4B) - A(4B) - A(4B) - A(4B) - A(4B) - ... - A(4B)

But, if we can guess that a directory will handle a number of child files,
we don't need to traverse the tree from level #0 to #N all the time.
Since the lower level tables contain relatively small number of dentries,
the miss ratio of the target dentry is likely to be high.

In order to avoid that, we can configure the hash tables sparsely from level #0
like this.

level #0   | A(2B) - A(2B) - A(2B) - A(2B)

level #1   | A(2B) - A(2B) - A(2B) - A(2B) - A(2B) - ... - A(2B)
     .     |   .       .       .       .
level #N/2 | A(2B) - A(2B) - A(2B) - A(2B) - A(2B) - ... - A(2B)
     .     |   .       .       .       .
level #N   | A(4B) - A(4B) - A(4B) - A(4B) - A(4B) - ... - A(4B)

With this structure, we can skip the ineffective tree searches in lower level
hash tables.

This patch adds just a facility for this by introducing i_dir_level in
f2fs_inode.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-02-27 19:56:09 +09:00
Jaegeuk Kim 3bac380c90 f2fs: update documents and a MAINTAINERS entry
This patch adds missing some description of sysfs entries in
 - Documentation/ABI/testing/sysfs-fs-f2fs
 - Documentation/filesystems/f2fs.txt.

And it adds a maintained document entry of F2FS in MAINTAINERS.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-01-09 21:00:06 +09:00
Huajun Li e4024e86c2 f2fs: update f2fs Documentation
This patch describes the inline_data support in f2fs document.

Signed-off-by: Huajun Li <huajun.li@intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-12-26 20:40:44 +09:00
Jaegeuk Kim ba0697ec98 f2fs: add description about small_discards in document
This patch adds a description about small_disacrds in the f2fs document.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-12-23 10:18:07 +09:00
Jaegeuk Kim 216fbd6443 f2fs: introduce sysfs entry to control in-place-update policy
This patch introduces new sysfs entries for users to control the policy of
in-place-updates, namely IPU, in f2fs.

Sometimes f2fs suffers from performance degradation due to its out-of-place
update policy that produces many additional node block writes.
If the storage performance is very dependant on the amount of data writes
instead of IO patterns, we'd better drop this out-of-place update policy.

This patch suggests 5 polcies and their triggering conditions as follows.

[sysfs entry name = ipu_policy]

0: F2FS_IPU_FORCE       all the time,
1: F2FS_IPU_SSR         if SSR mode is activated,
2: F2FS_IPU_UTIL        if FS utilization is over threashold,
3: F2FS_IPU_SSR_UTIL    if SSR mode is activated and FS utilization is over
                        threashold,
4: F2FS_IPU_DISABLE    disable IPU. (=default option)

[sysfs entry name = min_ipu_util]

This parameter controls the threshold to trigger in-place-updates.
The number indicates percentage of the filesystem utilization, and used by
F2FS_IPU_UTIL and F2FS_IPU_SSR_UTIL policies.

For more details, see need_inplace_update() in segment.h.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-12-23 10:18:07 +09:00
Jaegeuk Kim 66e960c692 f2fs: update f2fs document
This patch describes the inline_xattr support in f2fs document.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-11-01 11:20:05 +09:00
Jaegeuk Kim ea91e9b043 f2fs: add reclaiming control by sysfs
This patch adds a control method in sysfs to reclaim prefree segments.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-25 16:54:39 +09:00
Namjae Jeon d2dc095f42 f2fs: add sysfs entries to select the gc policy
Add sysfs entry gc_idle to control the gc policy. Where
gc_idle = 1 corresponds to selecting a cost benefit approach,
while gc_idle = 2 corresponds to selecting a greedy approach
to garbage collection. The selection is mutually exclusive one
approach will work at any point. If gc_idle = 0, then this
option is disabled.

Cc: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Pankaj Kumar <pankaj.km@samsung.com>
Reviewed-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
[Jaegeuk Kim: change the select_gc_type() flow slightly]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-08-06 22:00:18 +09:00
Namjae Jeon b59d0bae6c f2fs: add sysfs support for controlling the gc_thread
Add sysfs entries to control the timing parameters for
f2fs gc thread.

Various Sysfs options introduced are:
gc_min_sleep_time: Min Sleep time for GC in ms
gc_max_sleep_time: Max Sleep time for GC in ms
gc_no_gc_sleep_time: Default Sleep time for GC in ms

Cc: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Pankaj Kumar <pankaj.km@samsung.com>
Reviewed-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
[Jaegeuk Kim: fix an umount bug and some minor changes]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-08-06 21:53:34 +09:00
Changman Lee d51a7fba25 f2fs: add description for fsck.f2fs and dump.f2fs
This patch adds some description on fsck.f2fs and dump.f2fs which is
recently merged into f2fs-tools.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-07-30 15:17:02 +09:00
Namjae Jeon 696c018c77 f2fs: add remount_fs callback support
Add the f2fs_remount function call which will be used
during the filesystem remounting. This function
will help us to change the mount options specific to
f2fs.

Also modify the f2fs background_gc mount option, which
will allow the user to dynamically trun on/off the
garbage collection in f2fs based on the background_gc
value. If background_gc=on, Garbage collection will
be turned off & if background_gc=off, Garbage collection
will be truned on.

By default the garbage collection is on in f2fs.

Change Log:
v2: Incorporated the review comments by Gu Zheng.
    Removing the restore part for VFS flags
    Updating comments with proper flag conditions
    Display GC background option as ON/OFF
    Revised conditions to stop GC in case of remount

v1: Initial changes for adding remount_fs callback
support.

Cc: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Pankaj Kumar <pankaj.km@samsung.com>
Reviewed-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
[Jaegeuk Kim: change /** with /* for the coding style]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-06-17 21:17:55 +09:00
Changman Lee 1571f84a1f f2fs: update f2fs.txt related with discard at mkfs
o mkfs.f2fs supports no discard option.
 o fixed volume label size in 512 bytes.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-04-03 17:27:52 +09:00
Huajun Li 9268cc3523 f2fs: update f2fs document to reflect SIT/NAT layout correctly
document to reflect the layout generated by mkfs.f2fs .

Signed-off-by: Huajun Li <huajun.li.lee@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-01-04 09:42:59 +09:00
Huajun Li d08ab08d14 f2fs: fix a typo in f2fs documentation
In f2fs_fs.h, one f2fs inode contains 923 data block pointers, while
f2fs documentation says it is 929. Fix this inconsistence.

Signed-off-by: Huajun Li <huajun.li.lee@gmail.com>
2012-12-11 13:43:44 +09:00
Jaegeuk Kim 5bb446a289 f2fs: update the f2fs document
I moved the f2fs-tools.git into kernel.org.
And I added a new mailing list, linux-f2fs-devel@lists.sourceforge.net.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-11 13:43:42 +09:00
Jaegeuk Kim 98e4da8ca3 f2fs: add document
This adds a document describing the mount options, proc entries, usage, and
design of Flash-Friendly File System, namely F2FS.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-11 13:43:39 +09:00