21327a042d
SSR allocate mode will be used when doing file defragment
if ATGC is working at the same time, that is because
set_page_private_gcing may make CURSEG_ALL_DATA_ATGC segment
type got in f2fs_allocate_data_block when defragment page
is writeback, which may cause file fragmentation is worse.
A file with 2 fragmentations is changed as following after defragment:
----------------file info-------------------
sensorsdata :
--------------------------------------------
dev [254:48]
ino [0x 3029 : 12329]
mode [0x 81b0 : 33200]
nlink [0x 1 : 1]
uid [0x 27e6 : 10214]
gid [0x 27e6 : 10214]
size [0x 242000 : 2367488]
blksize [0x 1000 : 4096]
blocks [0x 1210 : 4624]
--------------------------------------------
file_pos start_blk end_blk blks
0 11361121 11361207 87
356352 11361215 11361216 2
364544 11361218 11361218 1
368640 11361220 11361221 2
376832 11361224 11361225 2
385024 11361227 11361238 12
434176 11361240 11361252 13
487424 11361254 11361254 1
491520 11361271 11361279 9
528384 3681794 3681795 2
536576 3681797 3681797 1
540672 3681799 3681799 1
544768 3681803 3681803 1
548864 3681805 3681805 1
552960 3681807 3681807 1
557056 3681809 3681809 1
Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.