=========================================================
¤³¤ì¤Ï¡¢
-Linux-2.6.31.1/Documentation/filesystems/ext4.txt ¤ÎÏÂÌõ
+linux-3.3/Documentation/filesystems/ext4.txt ¤ÎÏÂÌõ
¤Ç¤¹¡£
ËÝÌõÃÄÂΡ§ JF ¥×¥í¥¸¥§¥¯¥È < http://www.linux.or.jp/JF/ >
-¹¹¿·Æü ¡§ 2009/07/25
+¹¹¿·Æü ¡§ 2012/05/11
ËÝÌõ¼Ô ¡§ Seiji Kaneko < skaneko at mbn dot or dot jp >
ººÆÉ¼Ô : Hiroshi Suzuki <setter at reset dot jp>
=========================================================
#Note: More extensive information for getting started with ext4 can be
# found at the ext4 wiki site at the URL:
# http://ext4.wiki.kernel.org/index.php/Ext4_Howto
-Ãíµ: ext4 ¤ò¤Ï¤¸¤á¤ë¤ËÅö¤¿¤Ã¤Æ¤Î¤µ¤é¤Ë¾ÜºÙ¤ÊÀâÌÀ¤Ï¡¢²¼µ URL ¤Î ext4 Wiki
- ¥µ¥¤¥È¤Ë¤¢¤ê¤Þ¤¹¡£
+Ãíµ: ext4 ÍøÍѤò¤Ï¤¸¤á¤ë¤ËÅö¤¿¤Ã¤Æ¤Î¤µ¤é¤Ë¾ÜºÙ¤ÊÀâÌÀ¤Ï¡¢²¼µ URL ¤Î ext4
+ Wiki ¥µ¥¤¥È¤Ë¤¢¤ê¤Þ¤¹¡£
http://ext4.wiki.kernel.org/index.php/Ext4_Howto
# - Compile and install the latest version of e2fsprogs (as of this
# writing version 1.41.3) from:
- - ºÇ¿·¤Î e2fsprogs (¸½ºß¥Ð¡¼¥¸¥ç¥ó 1.41.3) ¤ò°Ê²¼¤«¤éÆþ¼ê¤·¡¢¥³¥ó¥Ñ¥¤¥ë¡¦
- ¥¤¥ó¥¹¥È¡¼¥ë¤·¤Æ¤¯¤À¤µ¤¤¡£
+ - ºÇ¿·¤Î e2fsprogs (ËÜʸ½ñ¼¹É®»þÅÀ¤Ç¤Ï¥Ð¡¼¥¸¥ç¥ó 1.41.3) ¤ò°Ê²¼¤«¤éÆþ¼ê
+ ¤·¡¢¥³¥ó¥Ñ¥¤¥ë¡¦¥¤¥ó¥¹¥È¡¼¥ë¤·¤Æ¤¯¤À¤µ¤¤¡£
http://sourceforge.net/project/showfiles.php?group_id=2406
# you will need to merge your changes with the version from e2fsprogs
# 1.41.x.
- e2fsprogs 1.41.x ¥½¡¼¥¹ÉÕ°¤Î mke2fs.conf ¥Õ¥¡¥¤¥ë¤ò /etc/mke2fs.conf
- ¤Ë¥¤¥ó¥¹¥È¡¼¥ë¤¹¤ë¤³¤È¤Ï¤È¤Æ¤â½ÅÍפǤ¹¡£¥·¥¹¥Æ¥à¤Ë¥¤¥ó¥¹¥È¡¼¥ë¤·¤Æ¤¢¤ë
- /etc/mke2fs.conf ¥Õ¥¡¥¤¥ë¤ò¤¹¤Ç¤ËÊÔ½¸¤·¤Æ¤¤¤ë¾ì¹ç¤Ï¡¢e2fsprogs 1.41.x
+ ¤Ë¥¤¥ó¥¹¥È¡¼¥ë¤¹¤ë¤³¤È¤¬¤È¤Æ¤â½ÅÍפǤ¹¡£¥·¥¹¥Æ¥à¤Ë¥¤¥ó¥¹¥È¡¼¥ë¤·¤Æ¤¢¤ë
+ /etc/mke2fs.conf ¥Õ¥¡¥¤¥ë¤ò¤¹¤Ç¤ËÊÔ½¸¤·¤Æ¤¤¤ë¾ì¹ç¤Ï¡¢e2fsprogs 1.41.x
¤ÎÈǤΤâ¤Î¤Ë´û¸¤Î½¤Àµ¤ò¥Þ¡¼¥¸¤¹¤ëɬÍפ¬¤¢¤ê¤Þ¤¹¡£
# - Create a new filesystem using the ext4 filesystem type:
# mke2fs -t ext4 /dev/hda1
-# Or to configure an existing ext3 filesystem to support extents:
- ¤Þ¤¿¤Ï¡¢´û¸¤Î ext3 ¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤ò¥¨¥¯¥¹¥Æ¥ó¥È¤ò¥µ¥Ý¡¼¥È¤¹¤ë¤è¤¦Àß
- Äꤷ¤Þ¤¹¡£
+# Or to configure an existing ext3 filesystem to support extents:
+ ¤Þ¤¿¤Ï¡¢´û¸¤Î ext3 ¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤ò¡¢¥¨¥¯¥¹¥Æ¥ó¥È¤ò¥µ¥Ý¡¼¥È¤¹¤ë¤è
+ ¤¦ÀßÄꤷ¤Þ¤¹¡£
# tune2fs -O extents /dev/hda1
# If the filesystem was created with 128 byte inodes, it can be
# converted to use 256 byte for greater efficiency via:
¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤¬ 128 ¥Ð¥¤¥È inode ¤ÇºîÀ®¤µ¤ì¤Æ¤¤¤ë¾ì¹ç¤Ï¡¢¸úΨ¤Î¤¿¤á
- 256 ¥Ð¥¤¥È¤ò»ÈÍѤ¹¤ë¤è¤¦°Ê²¼¤Î¤è¤¦¤ËÊÑ´¹¤Ç¤¤Þ¤¹¡£
+ 256 ¥Ð¥¤¥È (¤Þ¤¿¤Ï¤½¤ì°Ê¾å) ¤ò»ÈÍѤ¹¤ë¤è¤¦°Ê²¼¤Î¤è¤¦¤ËÊÑ´¹¤Ç¤¤Þ¤¹¡£
# tune2fs -I 256 /dev/hda1
# '-o barriers=[0|1]' mount option for both ext3 and ext4 filesystems
# for a fair comparison. When tuning ext3 for best benchmark numbers,
# it is often worthwhile to try changing the data journaling mode; '-o
-# data=writeback,nobh' can be faster for some workloads. (Note
-# however that running mounted with data=writeback can potentially
-# leave stale data exposed in recently written files in case of an
-# unclean shutdown, which could be a security exposure in some
-# situations.) Configuring the filesystem with a large journal can
-# also be helpful for metadata-intensive workloads.
+# data=writeback' can be faster for some workloads. (Note however that
+# running mounted with data=writeback can potentially leave stale data
+# exposed in recently written files in case of an unclean shutdown,
+# which could be a security exposure in some situations.) Configuring
+# the filesystem with a large journal can also be helpful for
+# metadata-intensive workloads.
- ¾¤Î¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤È¤ÎÀǽÈæ³Ó¤ÎºÝ¤Ï¡¢Ê£¿ô¤ÎÉé²Ù´Ä¶¤Ç»î¤¹¤³¤È¤¬¾ï¤Ë
½ÅÍפǤ¹¡£¥ï¡¼¥¯¥í¡¼¥É¥Ñ¥é¥á¡¼¥¿¤Î¤ï¤º¤«¤ÊÊѹ¹¤¬¡¢¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Î¾
¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤È¤ÎÈæ³Óɾ²Á¤Å¤±¤ò¤Þ¤Ã¤¿¤¯ÊѤ¨¤Æ¤·¤Þ¤¦¤³¤È¤¬ÉÑÈˤ˵¯¤³
- ¤ê¤Þ¤¹¡£ÆÃ¤Ë ext3 ¤È¤ÎÈæ³Ó¤Î¾ì¹ç¤Ï¡¢ext4 ¤¬½ñ¤¹þ¤ß¥Ð¥ê¥¢¤òɸ½à¤Ç͸ú
+ ¤ê¤Þ¤¹¡£ÆÃ¤Ë ext3 ¤È¤ÎÈæ³Ó¤Î¾ì¹ç¤Ï¡¢ext4 ¤¬¥é¥¤¥È¥Ð¥ê¥¢¤òɸ½à¤Ç͸ú
²½¤·¤Æ¤ª¤ê¡¢ext3 ¤Ïɸ½à¤Ç¤Ï¥é¥¤¥È¥Ð¥ê¥¢¤ò͸ú¤Ë¤·¤Æ¤Ï¤¤¤Ê¤¤¤³¤È¤Ëα°Õ
¤·¤Æ¤¯¤À¤µ¤¤¡£½¾¤Ã¤Æ¡¢¸øÊ¿¤ÊÈæ³Ó¤Î¤¿¤á¤Ë¤Ï¥é¥¤¥È¥Ð¥ê¥¢¤Î͸ú¡¦Ìµ¸ú¤òÌÀ
¼¨Åª¤Ë¡¢ext3 ¤È ext4 ¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤È¤â '-o barriers=[0|1]' ¤ò»È¤Ã¤Æ
»ØÄꤹ¤ë¤Î¤¬Ìò¤ËΩ¤Ä¤Ç¤·¤ç¤¦¡£ext4 ¤òºÇ¹â¤Î¥Ù¥ó¥Á¥Þ¡¼¥¯·ë²Ì¤È¤Ê¤ë¤è¤¦
¤Ë¥Á¥å¡¼¥Ë¥ó¥°¤¹¤ë¾ì¹ç¡¢¥Ç¡¼¥¿¥¸¥ã¡¼¥Ê¥ê¥ó¥°¥â¡¼¥É¤ÎÊѹ¹¤ò»î¤¹¤³¤È¤Ë¤Ï
- ²ÁÃͤ¬¤¢¤ê¤Þ¤¹¡£Î㤨¤Ð¡¢°ìÉô¤Î¥Ù¥ó¥Á¥Þ¡¼¥¯¤Ç¤Ï
- '-o data=writeback,nobh' ¤Ï¾¤è¤ê¹â®¤È¤Ê¤ë¤Ç¤·¤ç¤¦ (Ãí°Õ¤È¤·¤Æ¡¢
+ ²ÁÃͤ¬¤¢¤ê¤Þ¤¹¡£Î㤨¤Ð¡¢°ìÉô¤Î¥Ù¥ó¥Á¥Þ¡¼¥¯¤Ç¤Ï
+ '-o data=writeback' ¤Ï¾¤è¤ê¹â®¤È¤Ê¤ë¤Ç¤·¤ç¤¦ (Ãí°Õ¤È¤·¤Æ¡¢
data=writeback ¥â¡¼¥É¤Ç¥Þ¥¦¥ó¥È±¿ÍѤ·¤Æ¤¤¤ë¾ì¹ç¡¢¥¯¥ê¡¼¥ó¤Ç¤Ê¤¤¥·¥ã¥Ã
¥È¥À¥¦¥ó¤ÇľÁ°¤Ë½ñ¤¤¤¿¥Ç¡¼¥¿¤¬¥´¥ß¤È¤·¤Æ»Ä¤ë²ÄǽÀ¤¬¤¢¤ë¤¿¤á¡¢¾õ¶·¤Ë¤è
¤Ã¤Æ¤Ï¥»¥¥å¥ê¥Æ¥£Ì̤ǤξðÊóϳ±Ì¤Î²ÄǽÀ¤¬¤¢¤ê¤Þ¤¹)¡£¥¸¥ã¡¼¥Ê¥ë¤òÂç¤
#* Inode allocation using large virtual block groups via flex_bg
#* delayed allocation
#* large block (up to pagesize) support
-#* efficent new ordered mode in JBD2 and ext4(avoid using buffer head to force
+#* efficient new ordered mode in JBD2 and ext4(avoid using buffer head to force
# the ordering)
* 16TB Ķ¤Î¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤ÎÍøÍÑ (e2fsprogs ¤Ç¤Ï¤Þ¤À¥µ¥Ý¡¼¥È¤µ¤ì¤Æ¤¤¤Þ¤»¤ó)
* ¥á¥¿¥Ç¡¼¥¿¥ª¡¼¥Ð¥Ø¥Ã¥É (RAM, ¥¢¥¯¥»¥¹ I/O, ¥È¥é¥ó¥¶¥¯¥·¥ç¥ó) ¤ò¸º¤é¤¹¥¨¥¯
#[1] Filesystems with a block size of 1k may see a limit imposed by the
#directory hash tree having a maximum depth of two.
-[1] ¥Ö¥í¥Ã¥¯¥µ¥¤¥º 1k ¤Î¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Ç¤Ï¡¢¥Ç¥£¥ì¥¯¥È¥ê¥Ï¥Ã¥·¥å¥Ä¥ê¡¼¤¬ºÇÂç
-¿¼¤µ 2 ¤Ç¤¢¤ë¤³¤È¤«¤éÍè¤ëÀ©¸Â¤ËÀ©Ì󤵤ì¤Þ¤¹¡£
+[1] ¥Ö¥í¥Ã¥¯¥µ¥¤¥º 1k ¤Î¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Ç¤Ï¡¢¥Ç¥£¥ì¥¯¥È¥ê¥Ï¥Ã¥·¥å¥Ä¥ê¡¼¤¬
+ºÇÂ翼¤µ 2 ¤Ç¤¢¤ë¤³¤È¤«¤éÍè¤ëÀ©¸Â¤ËÀ©Ì󤵤ì¤Þ¤¹¡£
#2.2 Candidate features for future inclusion
2.2 ¾ÍèÄɲøõÊä¤Ëµó¤¬¤Ã¤Æ¤¤¤ëµ¡Ç½
#* Online defrag (patches available but not well tested)
* ¥ª¥ó¥é¥¤¥ó¥Ç¥Õ¥é¥° (¥Ñ¥Ã¥Á¤Ï¤¢¤ê¤Þ¤¹¤¬¡¢½½Ê¬¤Ë¤Ï¥Æ¥¹¥È¤µ¤ì¤Æ¤¤¤Þ¤»¤ó)
-#* reduced mke2fs time via lazy itable initialization in conjuction with
+#* reduced mke2fs time via lazy itable initialization in conjunction with
# the uninit_bg feature (capability to do this is available in e2fsprogs
# but a kernel thread to do lazy zeroing of unused inode table blocks
# after filesystem is first mounted is required for safety)
#partly a function of how much time everyone has to work on them. Features like
#metadata checksumming have been discussed and planned for a bit but no patches
#exist yet so I'm not sure they're in the near-term roadmap.
-¤³¤ì°Ê³°¤Ë¤â´ö¤Ä¤«¤Îµ¡Ç½¤¬¡¢ÁȤ߹þ¤ß¤Ë´Ø¤·¤ÆµÄÏÀÃæ¤Ç¤¹¡£µÄÏÀ¤Î·ë²Ì¤Ï¤½¤Îµ¡Ç½¤Ç
-¤³¤ì¤«¤éɬÍפʺî¶È»þ´Ö (¤Î¸«Ä̤·) ¤Ë°Í¸¤¹¤ë¤Ç¤·¤ç¤¦¡£¥á¥¿¥Ç¡¼¥¿¥Á¥§¥Ã¥¯¥µ¥à¤Î
-¤è¤¦¤Êµ¡Ç½¤ÏµÄÏÀ¤µ¤ì¤Æ¿¾¯¤Î·×²è¤â¤¢¤ê¤Þ¤¹¤¬¡¢¸½»þÅÀ¤Ç¤Ï¥Ñ¥Ã¥Á¤¬¤Ê¤¯¡¢¶á¤¤¾Íè
-¤Î¥í¡¼¥É¥Þ¥Ã¥×¤Ë¸½¤ï¤ì¤ë¤«¤É¤¦¤«¤ÏÄ꤫¤Ç¤Ï¤¢¤ê¤Þ¤»¤ó¡£
+¤³¤ì°Ê³°¤Ë¤â¡¢´ö¤Ä¤«¤Îµ¡Ç½¤ÎÁȤ߹þ¤ß¤Ë´Ø¤·¤ÆµÄÏÀÃæ¤Ç¤¹¡£µÄÏÀ¤Î·ë²Ì¤Ï¤½¤Îµ¡
+ǽ¤Ç¤³¤ì¤«¤éɬÍפʺî¶È»þ´Ö (¤Î¸«Ä̤·) ¤Ë°Í¸¤¹¤ë¤Ç¤·¤ç¤¦¡£¥á¥¿¥Ç¡¼¥¿¥Á¥§¥Ã
+¥¯¥µ¥à¤Î¤è¤¦¤Êµ¡Ç½¤ÏµÄÏÀ¤µ¤ì¤Æ¿¾¯¤Î·×²è¤â¤¢¤ê¤Þ¤¹¤¬¡¢¸½»þÅÀ¤Ç¤Ï¥Ñ¥Ã¥Á¤¬¤Ê
+¤¯¡¢¶á¤¤¾Íè¤Î¥í¡¼¥É¥Þ¥Ã¥×¤Ë¸½¤ï¤ì¤ë¤«¤É¤¦¤«¤ÏÄ꤫¤Ç¤Ï¤¢¤ê¤Þ¤»¤ó¡£
#The big performance win will come with mballoc, delalloc and flex_bg
#grouping of bitmaps and inode tables. Some test results available here:
¥Ó¥Ã¥È¥Þ¥Ã¥×¤È inode ¥Æ¡¼¥Ö¥ë¤Ëmballoc¡¢delalloc ¤È¡¢flex_bg ¥°¥ë¡¼¥Ô¥ó¥°
-¤òƳÆþ¤·¤¿¤³¤È¤Ë¤è¤êÂ礤ÊÀǽ²þÁ±¤¬¼Â¸½¤µ¤ì¤Æ¤¤¤Þ¤¹¡£Àǽ¬Äê·ë²Ì¤Î°ìÉô¤Ï
+¤òƳÆþ¤·¤¿¤³¤È¤Ë¤è¤ëÂ礤ÊÀǽ²þÁ±¤¬¼Â¸½¸«¹þ¤ß¤Ç¤¹¡£Àǽ¬Äê·ë²Ì¤Î°ìÉô¤Ï
°Ê²¼¤Ç¸ø³«¤µ¤ì¤Æ¤¤¤Þ¤¹¡£
- http://www.bullopensource.org/ext4/20080818-ffsb/ffsb-write-2.6.27-rc1.html
# writes to the filesystem.
ro ¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤ò¥ê¡¼¥É¥ª¥ó¥ê¡¼¤Ç¥Þ¥¦¥ó¥È¤¹¤ë¡£ext4
¤Ï¥ê¡¼¥É¥ª¥ó¥ê¡¼¤Ç¥Þ¥¦¥ó¥È¤·¤¿¾ì¹ç¤Ë¤â¥¸¥ã¡¼¥Ê¥ë¤Î¥ê
- ¥×¥ì¥¤¤ò¹Ô¤¦ (½¾¤Ã¤Æ¥Ñ¡¼¥Æ¥£¥·¥ç¥ó¤Ë½ñ¤¹þ¤ß¤ò¹Ô¤¦)
- ¤³¤È¤ËÃí°Õ¤·¤Æ¤¯¤À¤µ¤¤¡£¥Þ¥¦¥ó¥È¥ª¥×¥·¥ç¥ó
+ ¥×¥ì¥¤¤ò¹Ô¤¦ (½¾¤Ã¤Æ¥Ñ¡¼¥Æ¥£¥·¥ç¥ó¤Ë½ñ¤¹þ¤ß¤ò¹Ô¤¦)
+ ¤³¤È¤ËÃí°Õ¤·¤Æ¤¯¤À¤µ¤¤¡£¥Þ¥¦¥ó¥È¥ª¥×¥·¥ç¥ó
"ro,noload" ¤ò¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Ø¤Î½ñ¤¹þ¤ß¤òÁ˻ߤ¹
¤ë¤¿¤á¤Ë»ÈÍѤ¹¤ë¤³¤È¤¬¤Ç¤¤Þ¤¹¡£
»ØÄꤷ¤Þ¤¹¡£¥¸¥ã¡¼¥Ê¥ë¥Ç¥Ð¥¤¥¹¤Ï devnum ·Á¼°¤Ç¥¨¥ó¥³
¡¼¥É¤µ¤ì¤¿ major/minor ÈÖ¹æ¤Ç»ØÄꤵ¤ì¤Þ¤¹¡£
-#noload Don't load the journal on mounting. Note that
-# if the filesystem was not unmounted cleanly,
+#norecovery Don't load the journal on mounting. Note that
+#noload if the filesystem was not unmounted cleanly,
# skipping the journal replay will lead to the
# filesystem containing inconsistencies that can
# lead to any number of problems.
-noload ¥Þ¥¦¥ó¥È»þ¤Ë¥¸¥ã¡¼¥Ê¥ë¤ò¥í¡¼¥É¤·¤Þ¤»¤ó¡£¤â¤·¥Õ¥¡¥¤¥ë¥·¥¹
- ¥Æ¥à¤¬¥¯¥ê¡¼¥ó¤Ë¥¢¥ó¥Þ¥¦¥ó¥È¤µ¤ì¤Æ¤¤¤Ê¤«¤Ã¤¿¾ì¹ç¤Ë¤Ï¡¢¥¸
- ¥ã¡¼¥Ê¥ë¥ê¥×¥ì¥¤¤òÈô¤Ð¤¹¤³¤È¤Ë¤è¤ê¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤ËÉÔÀ°
- ¹ç¤¬È¯À¸¤¹¤ë¤Ç¤·¤ç¤¦¤·¡¢¤½¤Î·ë²ÌÍÍ¡¹¤ÊÌäÂ꤬µ¯¤¤ë¤Ç¤·¤ç
- ¤¦¡£
+norecovery ¥Þ¥¦¥ó¥È»þ¤Ë¥¸¥ã¡¼¥Ê¥ë¤ò¥í¡¼¥É¤·¤Þ¤»¤ó¡£¤â¤·¥Õ¥¡¥¤
+noload ¥ë¥·¥¹¥Æ¥à¤¬¥¯¥ê¡¼¥ó¤Ë¥¢¥ó¥Þ¥¦¥ó¥È¤µ¤ì¤Æ¤¤¤Ê¤«¤Ã¤¿
+ ¾ì¹ç¤Ë¤Ï¡¢¥¸¥ã¡¼¥Ê¥ë¥ê¥×¥ì¥¤¤òÈô¤Ð¤¹¤³¤È¤Ë¤è¤ê¥Õ¥¡
+ ¥¤¥ë¥·¥¹¥Æ¥à¤ËÉÔÀ°¹ç¤¬È¯À¸¤¹¤ë¤Ç¤·¤ç¤¦¤·¡¢¤½¤Î·ë²Ì
+ ÍÍ¡¹¤ÊÌäÂ꤬µ¯¤¤ë¤Ç¤·¤ç¤¦¡£
#data=journal All data are committed into the journal prior to being
-# written into the main file system.
+# written into the main file system. Enabling
+# this mode will disable delayed allocation and
+# O_DIRECT support.
data=journal Á´¥Ç¡¼¥¿¤Ï¡¢¥á¥¤¥ó¤Î¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Ë½ñ¤¹þ¤àÁ°¤Ë¡¢
- ¥¸¥ã¡¼¥Ê¥ë¤Ë¥³¥ß¥Ã¥È¤µ¤ì¤Þ¤¹¡£
+ ¥¸¥ã¡¼¥Ê¥ë¤Ë¥³¥ß¥Ã¥È¤µ¤ì¤Þ¤¹¡£¤³¤Î¥â¡¼¥É¤ò͸ú²½¤·
+ ¤¿¾ì¹ç¡¢ÃÙ±ä³ä¤êÅö¤Æ¤È O_DIRECT ¥µ¥Ý¡¼¥È¤Ï̵¸ú²½¤µ
+ ¤ì¤Þ¤¹¡£
#data=ordered (*) All data are forced directly out to the main file
# system prior to its metadata being committed to the
¤Î¥ª¥×¥·¥ç¥ó¤Ï¡¢Â¾¤Î ext4 ¥Þ¥¦¥ó¥È¥ª¥×¥·¥ç¥ó¤È¤Î°ì´Ó
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-#inode_readahead=n This tuning parameter controls the maximum
+#inode_readahead_blks=n This tuning parameter controls the maximum
# number of inode table blocks that ext4's inode
# table readahead algorithm will pre-read into
# the buffer cache. The default value is 32 blocks.
-inode_readahead=n ¤³¤Î¥Á¥å¡¼¥Ë¥ó¥°¥Ñ¥é¥á¡¼¥¿¤Ï¡¢ext4 inode ¥Æ¡¼¥Ö¥ëÀèÆÉ
- ¤ß¥¢¥ë¥´¥ê¥º¥à¤¬¥Ð¥Ã¥Õ¥¡¥¥ã¥Ã¥·¥å¤ËÀèÆɤߤ¹¤ë¡¢inode
- ¥Æ¡¼¥Ö¥ë¥Ö¥í¥Ã¥¯¤Î¿ô¤ÎºÇÂçÃͤòÀ©¸æ¤·¤Þ¤¹¡£´ûÄêÃÍ¤Ï 32
+inode_readahead_blks=n ¤³¤Î¥Á¥å¡¼¥Ë¥ó¥°¥Ñ¥é¥á¡¼¥¿¤Ï¡¢ext4 inode ¥Æ¡¼¥Ö¥ëÀèÆÉ
+ ¤ß¥¢¥ë¥´¥ê¥º¥à¤¬¥Ð¥Ã¥Õ¥¡¥¥ã¥Ã¥·¥å¤ËÀèÆɤߤ¹¤ë¡¢inode
+ ¥Æ¡¼¥Ö¥ë¥Ö¥í¥Ã¥¯¤Î¿ô¤ÎºÇÂçÃͤòÀ©¸æ¤·¤Þ¤¹¡£´ûÄêÃÍ¤Ï 32
¥Ö¥í¥Ã¥¯¤Ç¤¹¡£
-#orlov (*) This enables the new Orlov block allocator. It is
-# enabled by default.
-orlov (*) ¿·¤·¤¤¡¢Orlov ¥Ö¥í¥Ã¥¯¥¢¥í¥±¡¼¥¿¤ò͸ú¤Ë¤·¤Þ¤¹¡£¥Ç¥Õ
- ¥©¥ë¥È¤Ç͸ú¤Ç¤¹¡£
-
-#oldalloc This disables the Orlov block allocator and enables
-# the old block allocator. Orlov should have better
-# performance - we'd like to get some feedback if it's
-# the contrary for you.
-oldalloc Orlov ¥Ö¥í¥Ã¥¯¥¢¥í¥±¡¼¥¿¤ò̵¸ú¤Ë¤·¤Æ¡¢¸Å¤¤¥Ö¥í¥Ã¥¯¥¢
- ¥í¥±¡¼¥¿¤ò͸ú¤Ë¤·¤Þ¤¹¡£Orlov ¤ÎÊý¤¬Àǽ¤¬Îɤ¤¤Ï¤º¤Ç¤¹¤¬¡¢
- ¤â¤·¡¢µÕ¸ú²Ì¤Ê¤é¡¢ÃΤ餻¤Æ¤¯¤À¤µ¤¤¡£
-
-#user_xattr Enables Extended User Attributes. Additionally, you
-# need to have extended attribute support enabled in the
-# kernel configuration (CONFIG_EXT4_FS_XATTR). See the
-# attr(5) manual page and http://acl.bestbits.at/ to
-# learn more about extended attributes.
-user_xattr POSIX ³Èĥ°À¤ò͸ú¤Ë¤·¤Þ¤¹¡£Í¸ú¤Ë¤¹¤ë¤Ë¤Ï¡¢¤µ¤é¤Ë¥«¡¼
- ¥Í¥ëÀßÄê¤Ç³Èĥ°À¤Î¥µ¥Ý¡¼¥È (CONFIG_EXT4_FS_XATTR) ¤ò
- ÁȤ߹þ¤àɬÍפ¬¤¢¤ê¤Þ¤¹¡£
- POSIX ³Èĥ°À¤Î¾ÜºÙ¤ò³Ø¤Ö¤Ë¤Ï¡¢attr(5) ¤Î¥Þ¥Ë¥å¥¢¥ë¥Ú¡¼
- ¥¸¤È http://acl.bestbits.at ¤ò¸«¤Æ¤¯¤À¤µ¤¤¡£
-
-#nouser_xattr Disables Extended User Attributes.
+#nouser_xattr Disables Extended User Attributes. If you have extended
+# attribute support enabled in the kernel configuration
+# (CONFIG_EXT4_FS_XATTR), extended attribute support
+# is enabled by default on mount. See the attr(5) manual
+# page and http://acl.bestbits.at/ for more information
+# about extended attributes.
nouser_xattr POSIX ³Èĥ°À ¤ò̵¸ú¤Ë¤·¤Þ¤¹¡£
-
-#acl Enables POSIX Access Control Lists support.
-# Additionally, you need to have ACL support enabled in
-# the kernel configuration (CONFIG_EXT4_FS_POSIX_ACL).
-# See the acl(5) manual page and http://acl.bestbits.at/
-# for more information.
-acl POSIX ¥¢¥¯¥»¥¹À©¸æ¥ê¥¹¥È (POSIX ACL) ¥µ¥Ý¡¼¥È¤ò͸ú¤Ë
- ¤·¤Þ¤¹¡£Í¸ú¤Ë¤¹¤ë¤Ë¤Ï¡¢¤µ¤é¤Ë¥«¡¼¥Í¥ëÀßÄê¤Ç ACL ¤Î¥µ¥Ý
- ¡¼¥È (CONFIG_EXT4_FS_POSIX_ACL) ¤òÁȤ߹þ¤àɬÍפ¬¤¢¤ê
- ¤Þ¤¹¡£
- ACL ¤Î¾ÜºÙ¤Ï¡¢acl(5) ¤Î¥Þ¥Ë¥å¥¢¥ë¥Ú¡¼¥¸¤È
- http://acl.bestbits.at ¤ò¸«¤Æ¤¯¤À¤µ¤¤¡£
+ ¤â¤·¡¢³Èĥ°À¥µ¥Ý¡¼¥È¤¬¥«¡¼¥Í¥ëÀßÄê
+ (CONFIG_EXT4_FS_XATTR) ¤Ç͸ú¤Ë¤Ê¤Ã¤Æ¤¤¤ë¾ì¹ç¡¢ACL
+ ¤Ï¥Þ¥¦¥ó¥È»þ¤Ë¥Ç¥Õ¥©¥ë¥È¤Ç͸ú¤Ë¤Ê¤ê¤Þ¤¹¡£
+ POSIX ³Èĥ°À¤Î¾ÜºÙ¤ò³Ø¤Ö¤Ë¤Ï¡¢attr(5) ¤Î¥Þ¥Ë¥å¥¢
+ ¥ë¥Ú¡¼¥¸¤È http://acl.bestbits.at ¤ò¸«¤Æ¤¯¤À¤µ¤¤¡£
#noacl This option disables POSIX Access Control List
-# support.
-noacl POSIX ¥¢¥¯¥»¥¹À©¸æ¥ê¥¹¥È(POSIX ACL) ¤ò̵¸ú¤Ë¤·¤Þ¤¹¡£
-
-reservation
-
-noreservation
+# support. If ACL support is enabled in the kernel
+# configuration (CONFIG_EXT4_FS_POSIX_ACL), ACL is
+# enabled by default on mount. See the acl(5) manual
+# page and http://acl.bestbits.at/ for more information
+# about acl.
+noacl POSIX ¥¢¥¯¥»¥¹À©¸æ¥ê¥¹¥È(POSIX ACL) ¥µ¥Ý¡¼¥È¤ò̵¸ú
+ ¤Ë¤·¤Þ¤¹¡£¤â¤·¡¢ACL ¥µ¥Ý¡¼¥È¤¬¥«¡¼¥Í¥ëÀßÄê
+ (CONFIG_EXT4_FS_POSIX_ACL) ¤Ç͸ú¤Ë¤Ê¤Ã¤Æ¤¤¤ë¾ì¹ç¡¢
+ ACL ¤Ï¥Þ¥¦¥ó¥È»þ¤Ë¥Ç¥Õ¥©¥ë¥È¤Ç͸ú¤Ë¤Ê¤ê¤Þ¤¹¡£
+ acl ¤Ë¤Ä¤¤¤Æ¤Î¾ÜºÙ¤Ï acl(5) ¤Î¥Þ¥Ë¥å¥¢¥ë¥Ú¡¼¥¸¤ä¡¢
+ ¥¦¥§¥Ö¥µ¥¤¥È http://acl.bestbits.at/ ¤ò»²¾È¤¯¤À¤µ¤¤¡£
#bsddf (*) Make 'df' act like BSD.
#minixdf Make 'df' act like Minix.
#grpid Give objects the same group ID as their creator.
#bsdgroups
-grpid ¥ª¥Ö¥¸¥§¥¯¥È¤ÎºîÀ®»þ¤Ë¡¢ºîÀ®Àè¥Ç¥£¥ì¥¯¥È¥ê¤ÈƱ¤¸¥°¥ë¡¼¥×
-bsdgroups ID ¤òÍ¿¤¨¤Þ¤¹¡£
+grpid ¥ª¥Ö¥¸¥§¥¯¥È¤ÎºîÀ®»þ¤Ë¡¢ºîÀ®Àè¥Ç¥£¥ì¥¯¥È¥ê¤ÈƱ¤¸¥°
+bsdgroups ¥ë¡¼¥× ID ¤òÍ¿¤¨¤Þ¤¹¡£
#nogrpid (*) New objects have the group ID of their creator.
#sysvgroups
nogrpid (*) ¥ª¥Ö¥¸¥§¥¯¥È¤ÎºîÀ®»þ¤Ë¡¢ºîÀ®Àè¥Ç¥£¥ì¥¯¥È¥ê¤Ë setgid ¥Ó
sysvgroups ¥Ã¥È¤¬¥»¥Ã¥È¤µ¤ì¤Æ¤¤¤Ê¤¤¾ì¹ç¡¢ºîÀ®¥×¥í¥»¥¹¤ÈƱ¤¸¥°¥ë¡¼¥×
ID ¤òÍ¿¤¨¤Þ¤¹¡£ºîÀ®Àè¥Ç¥£¥ì¥¯¥È¥ê¤Ë setgid ¥Ó¥Ã¥È¤¬¥»¥Ã
- ¥È¤µ¤ì¤Æ¤¤¤¿¾ì¹ç¤Ë¤Ï¡¢ºîÀ®Àè¥Ç¥£¥ì¥¯¥È¥ê¤Î¥°¥ë¡¼¥× ID ¤È
- ºîÀ®¤µ¤ì¤¿¤Î¤¬¥Ç¥£¥ì¥¯¥È¥ê¤Ç¤¢¤Ã¤¿¾ì¹ç¤Ë¤Ï setgid ¥Ó¥Ã¥È
- ¤¬°ú¤·Ñ¤¬¤ì¤Þ¤¹¡£
+ ¥È¤µ¤ì¤Æ¤¤¤¿¾ì¹ç¤Ë¤Ï¡¢ºîÀ®Àè¥Ç¥£¥ì¥¯¥È¥ê¤Î¥°¥ë¡¼¥×
+ ID ¤¬°ú¤·Ñ¤¬¤ì¡¢¹¹¤ËºîÀ®¤µ¤ì¤¿¤Î¤¬¥Ç¥£¥ì¥¯¥È¥ê¤Ç¤¢
+ ¤Ã¤¿¾ì¹ç¤Ë¤Ï setgid ¥Ó¥Ã¥È¤â°ú¤·Ñ¤¬¤ì¤Þ¤¹¡£
#resgid=n The group ID which may use the reserved blocks.
-resgid=n ͽÌó¥Ö¥í¥Ã¥¯¤ò»ÈÍѤ¹¤ë¥°¥ë¡¼¥× ID ¤Ç¤¹¡£
+resgid=n ͽÌó¥Ö¥í¥Ã¥¯¤ò»ÈÍѤ·¤Æ¤è¤¤¥°¥ë¡¼¥× ID ¤Ç¤¹¡£
#resuid=n The user ID which may use the reserved blocks.
-resuid=n ͽÌó¥Ö¥í¥Ã¥¯¤ò»ÈÍѤ¹¤ë¥æ¡¼¥¶ ID ¤Ç¤¹¡£
+resuid=n ͽÌó¥Ö¥í¥Ã¥¯¤ò»ÈÍѤ·¤Æ¤è¤¤¥æ¡¼¥¶ ID ¤Ç¤¹¡£
#sb=n Use alternate superblock at this location.
sb=n ¤³¤Î°ÌÃÖ¤ÎÂåÂØ¥¹¡¼¥Ñ¡¼¥Ö¥í¥Ã¥¯¤ò»È¤¤¤Þ¤¹¡£
-quota
-noquota
-grpquota
-usrquota
-
-#bh (*) ext4 associates buffer heads to data pages to
-#nobh (a) cache disk block mapping information
-# (b) link pages into transaction to provide
-# ordering guarantees.
-# "bh" option forces use of buffer heads.
-# "nobh" option tries to avoid associating buffer
-# heads (supported only for "writeback" mode).
-bh (*) ext4 ¤Ï¥Ð¥Ã¥Õ¥¡ÀèƬ¤ò°Ê²¼¤Î¾ðÊó¤Ë´ØÏ¢¤Å¤±¤Þ¤¹¡£
-nobh (a) ¥¥ã¥Ã¥·¥å¥Ç¥£¥¹¥¯¥Ö¥í¥Ã¥¯¥Þ¥Ã¥×¾ðÊó
- (b) ½ç½øÊݾڤΤ¿¤á¤Î¥È¥é¥ó¥¶¥¯¥·¥ç¥óÆâ¤Î¥ê¥ó¥¯¥Ú¡¼¥¸
- bh ¥ª¥×¥·¥ç¥ó¤Ç¤Ï¥Ð¥Ã¥Õ¥¡¥Ø¥Ã¥É¤ÎÍøÍѤò¶¯À©¤·¡¢nobh
- ¥ª¥×¥·¥ç¥ó¤Ç¤Ï¥Ð¥Ã¥Õ¥¡ÀèƬ¤È¤Î´ØÏ¢¤Å¤±¤òÈò¤±¤Þ¤¹
- (writeback ¥â¡¼¥É¤Ç¤Î¤ß¥µ¥Ý¡¼¥È¤µ¤ì¤Þ¤¹)¡£
+#quota These options are ignored by the filesystem. They
+#noquota are used only by quota tools to recognize volumes
+#grpquota where quota should be turned on. See documentation
+#usrquota in the quota-tools package for more details
+# (http://sourceforge.net/projects/linuxquota).
+quota ¤³¤Î¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Ç¤Ï¡¢¤³¤ì¤é¤Î¥ª¥×¥·¥ç¥ó¤Ï̵»ë¤µ¤ì
+noquota ¤Þ¤¹¡£¤³¤ì¤é¥Õ¥é¥°¤Ï Quota ¤ò͸ú¤Ë¤¹¤Ù¤¾ì¹ç¤Ë¡¢Quota
+grpquota ¥Ä¡¼¥ë¤Ç¥Ü¥ê¥å¡¼¥à¤òǧ¼±¤¹¤ë¤¿¤á¤Ë¤Î¤ßÍøÍѤµ¤ì¤Þ¤¹¡£
+usrquota ¾Ü¤·¤¯¤Ï quota-tools ¥Ñ¥Ã¥±¡¼¥¸Æ±º¤Îʸ½ñ¤ò»²¾È¤¯¤À¤µ¤¤¡£
+ (http://sourceforge.net/projects/linuxquota).
+
+#jqfmt=<quota type> These options tell filesystem details about quota
+#usrjquota=<file> so that quota information can be properly updated
+#grpjquota=<file> during journal replay. They replace the above
+# quota options. See documentation in the quota-tools
+# package for more details
+# (http://sourceforge.net/projects/linuxquota).
+jqfmt=<quota type> ¤³¤ì¤é¤Î¥ª¥×¥·¥ç¥ó¤Ï¥¸¥ã¡¼¥Ê¥ë¥ê¥×¥ì¥¤»þ¤Ë Quota ¾ðÊó
+usrjquota=<file> ¤¬Àµ¤·¤¯¹¹¿·¤µ¤ì¤ë¤è¤¦¡¢¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Ë Quota ¤Î¾Ü
+grpjquota=<file> ºÙ¤ò»ØÄꤹ¤ë¤¿¤á¤Î¤â¤Î¤Ç¤¹¡£¤³¤ì¤é¤Ï¾åµ¤Î quota ¥ª¥×
+ ¥·¥ç¥ó¤òÃÖ¤´¹¤¨¤Þ¤¹¡£
+ ¾Ü¤·¤¯¤Ï quota-tools ¥Ñ¥Ã¥±¡¼¥¸Æ±º¤Îʸ½ñ¤ò»²¾È¤¯¤À¤µ¤¤¡£
+ (http://sourceforge.net/projects/linuxquota).
#stripe=n Number of filesystem blocks that mballoc will try
# to use for allocation size and alignment. For RAID5/6
# systems this should be the number of data
# disks * RAID chunk size in file system blocks.
-#delalloc (*) Deferring block allocation until write-out time.
-#nodelalloc Disable delayed allocation. Blocks are allocation
-# when data is copied from user to page cache.
stripe=n mballoc ¤¬¥¢¥í¥±¡¼¥·¥ç¥óñ°Ì¤È¥¢¥é¥¤¥ó¤Ë»ÈÍѤ·¤è¤¦¤È
¤¹¤ë¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¥Ö¥í¥Ã¥¯¿ô¤Ç¤¹¡£RAID5/6 ¤Ç¤Ï¡¢¤³
¤ÎÃͤϥǡ¼¥¿¥Ç¥£¥¹¥¯¿ô¤È¡¢¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¥Ö¥í¥Ã¥¯¤Î
RAID ¥Á¥ã¥ó¥¯¥µ¥¤¥º¤È¤ÎÀѤˤ¹¤Ù¤¤Ç¤¹¡£
-delalloc (*) ½ñ¤¹þ¤ß»þ¤Þ¤Ç¥Ö¥í¥Ã¥¯³ä¤êÅö¤Æ¤òÃٱ䤵¤»¤Þ¤¹¡£
-nodelalloc ÃÙ±ä³ä¤êÅö¤Æ¤ò̵¸ú¤Ë¤·¤Þ¤¹¡£¥Ç¡¼¥¿¤¬¥æ¡¼¥¶¤«¤é¥Ú¡¼¥¸
+
+#delalloc (*) Defer block allocation until just before ext4
+# writes out the block(s) in question. This
+# allows ext4 to better allocation decisions
+# more efficiently.
+#nodelalloc Disable delayed allocation. Blocks are allocated
+# when the data is copied from userspace to the
+# page cache, either via the write(2) system call
+# or when an mmap'ed page which was previously
+# unallocated is written for the first time.
+delalloc (*) ext4 ¤¬Âоݥ֥í¥Ã¥¯¤ò½ñ¤¹þ¤àľÁ°¤Þ¤Ç¥Ö¥í¥Ã¥¯³ä¤êÅö
+ ¤Æ¤òÃٱ䤵¤»¤Þ¤¹¡£¤³¤ì¤Ë¤è¤ê¡¢ext4 ¤Î³ä¤êÅö¤ÆȽÃǤ¬
+ ²þÁ±¤«¤Ä¸úΨ²½¤µ¤ì¤Þ¤¹¡£
+nodelalloc ÃÙ±ä³ä¤êÅö¤Æ¤ò̵¸ú¤Ë¤·¤Þ¤¹¡£write(2) ¥·¥¹¥Æ¥à¥³¡¼¥ë¡¢
+ ¤Þ¤¿¤Ï̤³ä¤êÅö¤Æ¤À¤Ã¤¿ mmap ¤µ¤ì¤Æ¤¤¤ë¥Ú¡¼¥¸¤¬ºÇ½é¤Ë
+ ½ñ¤¹þ¤Þ¤ì¤ë¤³¤È¤Ë¤è¤Ã¤Æ¡¢¥Ç¡¼¥¿¤¬¥æ¡¼¥¶¤«¤é¥Ú¡¼¥¸
¥¥ã¥Ã¥·¥å¤Ë½ñ¤¹þ¤Þ¤ì¤¿»þÅÀ¤Ç¥Ö¥í¥Ã¥¯³ä¤êÅö¤Æ¤¬¹Ô¤Ê
¤ï¤ì¤Þ¤¹¡£
¤ë»þ´Ö (Ê¿¶Ñ»þ´Ö) ¤ò¬Äꤹ¤ë¤³¤È¤Ë¤è¤ê¡¢¥Ç¥£¥¹¥¯Â®ÅÙ¤Ë
ºÇŬ²½¤¹¤ë¤è¤¦À߷פµ¤ì¤¿¤â¤Î¤Ç¤¹¡£¤³¤³¤Ç¾åµ¤Î¡Ö¥³¥ß¥Ã
¥È´°Î»¤ËÍפ¹¤ë»þ´Ö¡×¤ò ¡ÉCommit time" ¤È¸Æ¤Ö¤³¤È¤Ë¤·¤Þ
- ¤¹¡£¤â¤·¡¢¥È¥é¥ó¥¶¥¯¥·¥ç¥ó¤ò¼Â¹Ô¤·¤Æ¤¤¤ë»þ´Ö¤¬ Commit
+ ¤¹¡£¤â¤·¡¢¥È¥é¥ó¥¶¥¯¥·¥ç¥ó¤ò¼Â¹Ô¤·¤Æ¤¤¤ë»þ´Ö¤¬ Commit
time ¤è¤ê¾®¤µ¤¤¤Ê¤é¤Ð¡¢ext4 ¤Ï Commit time ¤À¤±¥¹¥ê¡¼
¥×¤·¤Æ¾¤Î½èÍý¤¬¥È¥é¥ó¥¶¥¯¥·¥ç¥ó¤Ë¹çή¤Ç¤¤ë¤«¤É¤¦¤«¤ò
Ä´¤Ù¤Þ¤¹¡£¤³¤Î Commit time ¤Ï max_batch_time ¤Ë¤è¤ê
- ¾å¸Â¤¬»ØÄꤵ¤ì¤Þ¤¹¡£max_batch_time ¤Îɸ½àÃͤÏ
+ ¾å¸Â¤¬»ØÄꤵ¤ì¤Þ¤¹¡£max_batch_time ¤Îɸ½àÃͤÏ
15000us (15ms) ¤Ç¤¹¡£max_batch_time ¤ò 0 ¤È»ØÄꤹ¤ë
¤³¤È¤Ç¡¢¤³¤ÎºÇŬ²½¤ò´°Á´¤Ë̵¸ú²½¤Ç¤¤Þ¤¹¡£
# multi-threaded, synchronous workloads on very
# fast disks, at the cost of increasing latency.
min_batch_time=usec ¤³¤Î¥Ñ¥é¥á¡¼¥¿¤Ï commit time (¾åµ»²¾È) ¤¬¡¢¾¯¤Ê¤¯¤È¤â
- min_batch_time °Ê¾å¤Ç¤¢¤ë¤³¤È¤ò»ØÄꤷ¤Þ¤¹¡£É¸½àÃÍ¤Ï 0
+ min_batch_time °Ê¾å¤Ç¤¢¤ë¤³¤È¤ò»ØÄꤷ¤Þ¤¹¡£É¸½àÃÍ¤Ï 0
ms ¤Ç¤¹¡£¤³¤Î¥Ñ¥é¥á¡¼¥¿¤òÁý¤ä¤·¤¿¾ì¹ç¡¢¥Þ¥ë¥Á¥¹¥ì¥Ã¥É¤Ç
Ʊ´ü¤ò»È¤¦½èÍýÉé²Ù¤ò¹â®¤Ê¥Ç¥£¥¹¥¯¤Ç¼Â¹Ô¤·¤Æ¤¤¤ë¾ì¹ç¡¢¥ì
¥¤¥Æ¥ó¥·¥£¤ÎÁý²Ã¤Î¥³¥¹¥È¤òÂå½þ¤Ë¥¹¥ë¡¼¥×¥Ã¥È¤¬²þÁ±¤·¤Þ¤¹¡£
# priority.
journal_ioprio=prio kjournald2 ¤¬¡¢¥³¥ß¥Ã¥È½èÍýÃæ¤Ëȯ¹Ô¤¹¤ë I/O ½èÍý¤ÇÍѤ¤
¤ë I/O ¥×¥é¥¤¥ª¥ê¥Æ¥£ (0 ¤«¤é 7 ¤Ç¡¢0 ¤¬ºÇ¹â¤Î¥×¥é¥¤¥ª
- ¥ê¥Æ¥£¤Ç¤¹) ¤ò»ØÄꤷ¤Þ¤¹¡£É¸½àÃÍ¤Ï 3 ¤Ç¡¢¤³¤ì¤ÏÄ̾ï¤Î
+ ¥ê¥Æ¥£¤Ç¤¹) ¤ò»ØÄꤷ¤Þ¤¹¡£É¸½àÃÍ¤Ï 3 ¤Ç¡¢¤³¤ì¤ÏÄ̾ï¤Î
I/O ¥×¥é¥¤¥ª¥ê¥Æ¥£¤è¤ê¾¯¤·¹â¤¯¤Ê¤Ã¤Æ¤¤¤Þ¤¹¡£
-#auto_da_alloc(*) Many broken applications don't use fsync() when
+#auto_da_alloc(*) Many broken applications don't use fsync() when
#noauto_da_alloc replacing existing files via patterns such as
# fd = open("foo.new")/write(fd,..)/close(fd)/
# rename("foo.new", "foo"), or worse yet,
# blocks are forced to disk.
auto_da_alloc(*) ¿¤¯¤Î²õ¤ì¤¿¥¢¥×¥ê¥±¡¼¥·¥ç¥ó¤Ï¡¢fd = open("foo.new")/
noauto_da_alloc write(fd,..)/close(fd)/rename("foo.new", "foo") ¤Ê
- ¤É¤Î¥Ñ¥¿¡¼¥ó¡¢¤¢¤ë¤¤¤Ï¤½¤ì¤è¤ê¼Ù°¤Ê
- fd = open("foo", O_TRUNC)/write(fd,..)/close(fd)
+ ¤É¤Î¥Ñ¥¿¡¼¥ó¡¢¤¢¤ë¤¤¤Ï¤½¤ì¤è¤ê¼Ù°¤Ê
+ fd = open("foo", O_TRUNC)/write(fd,..)/close(fd)
¥Ñ¥¿¡¼¥ó¤Ç¡¢fsync() ¤ò»È¤ï¤Ê¤¤¤Ç´û¸¤Î¥Õ¥¡¥¤¥ë¤òÆþ¤ì
Âؤ¨¤Þ¤¹¡£auto_da_alloc ¤¬Í¸ú¤Ê¾ì¹ç¡¢ext4 ¤Ï¤³¤Î¥ê
¥Í¡¼¥à¤Ë¤è¤ë¥Õ¥¡¥¤¥ë¤ÎÆþ¤ìÂؤ¨¤È truncate ¤Ë¤è¤ë¥Õ¥¡
¤ëÁ°¤Ë¥·¥¹¥Æ¥à¤¬¥¯¥é¥Ã¥·¥å¤·¤¿¾ì¹ç¤Î¡ÖŤµ 0 ¤Ë¤Ê¤ë¡×
ÌäÂê¤ò (ƱÄøÅÙ¤Ë) ²óÈò¤Ç¤¤Þ¤¹¡£
+#noinit_itable Do not initialize any uninitialized inode table
+# blocks in the background. This feature may be
+# used by installation CD's so that the install
+# process can complete as quickly as possible; the
+# inode table initialization process would then be
+# deferred until the next time the file system
+# is unmounted.
+noinit_itable ½é´ü²½¤µ¤ì¤Æ¤¤¤Ê¤¤ inode ¥Æ¡¼¥Ö¥ë¤ò¥Ð¥Ã¥¯¥°¥é¥¦¥ó¥É
+ ¤Ç½é´ü²½¤·¤Þ¤»¤ó¡£¤³¤Îµ¡Ç½¤Ï¡¢¥¤¥ó¥¹¥È¡¼¥ë CD Åù¤Ç
+ ²Äǽ¤Ê¸Â¤ê®¤¯¥¤¥ó¥¹¥È¡¼¥ë¤ò½ªÎ»¤Ç¤¤ë¤è¤¦¤Ë¤¹¤ëºÝ
+ ¤ËÍѤ¤¤ë¤³¤È¤¬¤Ç¤¤Þ¤¹¡£inode ¥Æ¡¼¥Ö¥ë¤Î½é´ü²½½èÍý¤Ï
+ ¼¡¤Ë¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤¬ unmount ¤µ¤ì¤ë¤Þ¤Ç±ä´ü¤µ¤ì¤Þ¤¹¡£
+
+#init_itable=n The lazy itable init code will wait n times the
+# number of milliseconds it took to zero out the
+# previous block group's inode table. This
+# minimizes the impact on the systme performance
+# while file system's inode table is being initialized.
+init_itable=n itable ¤ÎÃÙ±ä½é´ü²½¥³¡¼¥É¤Ï¡¢Á°¤Î inode ¥Æ¡¼¥Ö¥ë¥Ö¥í
+ ¥Ã¥¯¤Î 0 ¥¯¥ê¥¢¸å¡¢n ¥ß¥êÉÃÂԤäƼ¡¤Î½é´ü²½¤ò¼Â¹Ô¤·¤Þ
+ ¤¹¡£¤³¤ì¤Ï¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Î inode ¥Æ¡¼¥Ö¥ë¤Î½é´ü²½½è
+ Íý¤¬¥·¥¹¥Æ¥à¤ÎÀǽ¤ËÍ¿¤¨¤ë±Æ¶Á¤òºÇ¾®¸Â¤ËÍÞ¤¨¤Þ¤¹¡£
+
+#discard Controls whether ext4 should issue discard/TRIM
+#nodiscard(*) commands to the underlying block device when
+# blocks are freed. This is useful for SSD devices
+# and sparse/thinly-provisioned LUNs, but it is off
+# by default until sufficient testing has been done.
+discard ext4 ¤¬ discard/TRIM ¥³¥Þ¥ó¥É¤òȯ¹Ô¤¹¤ë¤«Èݤ«¤òÀ©¸æ
+nodiscard(*) ¤·¤Þ¤¹¡£¤³¤Î¥³¥Þ¥ó¥É¤Ï¥Ö¥í¥Ã¥¯³«Êü»þ¤Ë²¼°Ì¤Î¥Ç¥Ð¥¤¥¹
+ ¤ËÂФ·¤Æȯ¹Ô¤µ¤ì¤Þ¤¹¡£¤³¤ì¤Ï SSD ¥Ç¥Ð¥¤¥¹¤ä¡¢¥¹¥Ñ¡¼
+ ¥¹¤Þ¤¿¤Ï¥·¥ó¥×¥í¥Ó¥¸¥ç¥Ë¥ó¥°¤òÍѤ¤¤¿ LUN ¤ÇÌò¤ËΩ¤Á
+ ¤Þ¤¹¤¬¡¢¸½ºß½½Ê¬¤Ê¥Æ¥¹¥È¤¬¤Ê¤µ¤ì¤Æ¤¤¤Ê¤¤¤Î¤Ç¡¢É¸½àÃÍ
+ ¤Ï off ¤Ë¤Ê¤Ã¤Æ¤¤¤Þ¤¹¡£
+
+#nouid32 Disables 32-bit UIDs and GIDs. This is for
+# interoperability with older kernels which only
+# store and expect 16-bit values.
+nouid32 32-bit UID ¤È GID ¤ò»È¤ï¤Ê¤¤¤è¤¦¤Ë¤·¤Þ¤¹¡£¤³¤ì¤Ï¡¢
+ 16 bit ÃͤΤߤò½ñ¤¹þ¤ß¡¢ÍøÍѤ¹¤ë¸Å¤¤¥«¡¼¥Í¥ë¤È¤Î¸ß
+ ´¹À¤Î¤¿¤á¤Î¤â¤Î¤Ç¤¹¡£
+
+#resize Allows to resize filesystem to the end of the last
+# existing block group, further resize has to be done
+# with resize2fs either online, or offline. It can be
+# used only with conjunction with remount.
+resize ºÇ½ª¤Î»ÈÍѺѤߤΥ֥í¥Ã¥¯¥°¥ë¡¼¥×¤Ø¤Î¥ê¥µ¥¤¥º¤òµö¤·
+ ¤Þ¤¹¡£¤³¤ì°Ê¾å¤Î¥ê¥µ¥¤¥º¤Ï¡¢¥ª¥ó¥é¥¤¥ó¤Þ¤¿¤Ï¥ª¥Õ¥é
+ ¥¤¥ó¤Ç resize2fs¤òÍѤ¤¤Æ¹Ô¤¦É¬Íפ¬¤¢¤ê¤Þ¤¹¡£¥ê¥µ¥¤
+ ¥º¸å¤Î¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Ï remount ¸å¤ËÍøÍѲÄǽ¤Ë¤Ê¤ê
+ ¤Þ¤¹¡£
+
+#block_validity This options allows to enables/disables the in-kernel
+#noblock_validity facility for tracking filesystem metadata blocks
+# within internal data structures. This allows multi-
+# block allocator and other routines to quickly locate
+# extents which might overlap with filesystem metadata
+# blocks. This option is intended for debugging
+# purposes and since it negatively affects the
+# performance, it is off by default.
+block_validity ¤³¤Î¥ª¥×¥·¥ç¥ó¤Ï¡¢¥«¡¼¥Í¥ëÆâ¤ÎÆâÉô¥Ç¡¼¥¿¹½Â¤¤ËÁȤß
+noblock_validity ¹þ¤Þ¤ì¤¿¥á¥¿¥Ç¡¼¥¿¥Ö¥í¥Ã¥¯¤ÎÄÉÀ×µ¡Ç½¤ò¡¢Í¸ú/̵¸ú¤Ë
+ ¤¹¤ë¤â¤Î¤Ç¤¹¡£¤³¤ÎÄÉÀ×µ¡Ç½¤Ï¡¢Ê£¿ô¥Ö¥í¥Ã¥¯¤Î¥¢¥í¥±
+ ¡¼¥¿¤Ê¤É¤Î½èÍý¤Ç¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¥á¥¿¥Ç¡¼¥¿¥Ö¥í¥Ã¥¯
+ ¤È½Å¤Ê¤ë²ÄǽÀ¤Î¤¢¤ëÎΰè¤Ë¤¢¤ë¥¨¥¯¥¹¥Æ¥ó¥È¤òÁÇÁ᤯
+ ¸«¤Ä¤±¤ë¤¿¤á¤Î¤â¤Î¤Ç¤¹¡£
+ ¤³¤Î¥ª¥×¥·¥ç¥ó¤Ï¥Ç¥Ð¥Ã¥°ÍѤÎÌÜŪ¤Î¤â¤Î¤Ç¡¢Àǽ¤ËÉé
+ ¤Î±Æ¶Á¤òÍ¿¤¨¤Þ¤¹¡£É¸½à¤Ç¤Ï¥ª¥Õ¤Ë¤Ê¤Ã¤Æ¤¤¤Þ¤¹¡£
+
+#dioread_lock Controls whether or not ext4 should use the DIO read
+#dioread_nolock locking. If the dioread_nolock option is specified
+# ext4 will allocate uninitialized extent before buffer
+# write and convert the extent to initialized after IO
+# completes. This approach allows ext4 code to avoid
+# using inode mutex, which improves scalability on high
+# speed storages. However this does not work with
+# data journaling and dioread_nolock option will be
+# ignored with kernel warning. Note that dioread_nolock
+# code path is only used for extent-based files.
+# Because of the restrictions this options comprises
+# it is off by default (e.g. dioread_lock).
+dioread_lock ext4 ¤¬ DIO ¥ê¡¼¥É¥í¥Ã¥¯¤ò»È¤¦¤«¤É¤¦¤«¤òÀ©¸æ¤·¤Þ¤¹¡£
+dioread_nolock ¤â¤· dioread_nolock ¥ª¥×¥·¥ç¥ó¤¬»ØÄꤵ¤ì¤Æ¤¤¤ë¾ì¹ç
+ ¤Ï¡¢ext4 ¤Ï¥Ð¥Ã¥Õ¥¡¥é¥¤¥ÈÁ°¤Ë̤½é´ü²½¾õÂ֤Υ¨¥¯¥¹¥Æ
+ ¥ó¥È¤ò³ä¤êÅö¤Æ¡¢IO ½ªÎ»¸å¤Ë¥¨¥¯¥¹¥Æ¥ó¥È¤ò½é´ü²½¾õÂÖ
+ ¤ËÊѹ¹¤·¤Þ¤¹¡£¤³¤Î¼ê½ç¤Ë¤è¤ê¡¢ext4 ¤Ç inode mutex
+ ¤ò»È¤ï¤Ê¤¤¤ÇºÑ¤à¤è¤¦¤Ë¤Ê¤ë¤¿¤á¡¢¹â®¤Ê¥¹¥È¥ì¡¼¥¸¤ò
+ »È¤Ã¤¿¾ì¹ç¤Î¥·¥¹¥Æ¥à¤Î³ÈÄ¥À¤¬¸þ¾å¤·¤Þ¤¹¡£¤¿¤À¤·¡¢
+ ¤³¤Îµ¡Ç½¤Ï¥Ç¡¼¥¿¥¸¥ã¡¼¥Ê¥ê¥ó¥°¤È¶¦¤Ë¤Ï»È¤¨¤º¡¢¥Ç¡¼
+ ¥¿¥¸¥ã¡¼¥Ê¥ê¥ó¥°¤¬Í¸ú¤Ê¾ì¹ç¤Ë¤Ï dioread_nolock ¥ª
+ ¥×¥·¥ç¥ó¤Ï¥«¡¼¥Í¥ë·Ù¹ð¥á¥Ã¥»¡¼¥¸¤ò½Ð¤·¤Æ̵»ë¤µ¤ì¤ë
+ ¤³¤È¤Ë¤Ê¤ê¤Þ¤¹¡£¤³¤Î dioread_nolock ¥³¡¼¥É½èÍý¤Ï¥¨
+ ¥¯¥¹¥Æ¥ó¥È¥Ù¡¼¥¹¤Î¥Õ¥¡¥¤¥ë¤Ç¤Î¤ßÍѤ¤¤é¤ì¤ë¤³¤È¤Ëα
+ °Õ¤¯¤À¤µ¤¤¡£¤³¤Î¥ª¥×¥·¥ç¥ó¤Ëȼ¤¦À©Ìó¤Î¤¿¤á¡¢É¸½à¤Ç
+ ¤Ï¥ª¥Õ (¤Ä¤Þ¤ê dioread_lock ¥â¡¼¥É) ¤Ë¤Ê¤Ã¤Æ¤¤¤Þ¤¹¡£
+#i_version Enable 64-bit inode version support. This option is
+# off by default.
+i_version 64-bit inode ¥Ð¡¼¥¸¥ç¥ó¤Î¥µ¥Ý¡¼¥È¤ò͸ú¤Ë¤·¤Þ¤¹¡£
+ ¤³¤Î¥ª¥×¥·¥ç¥ó¤Ï¡¢É¸½à¤Ç¤Ï¥ª¥Õ¤Ë¤Ê¤Ã¤Æ¤¤¤Þ¤¹¡£
+
#Data Mode
#=========
¥Ç¡¼¥¿¥â¡¼¥É
#mode - metadata journaling. A crash+recovery can cause incorrect data to
#appear in files which were written shortly before the crash. This mode will
#typically provide the best ext4 performance.
-* ¥é¥¤¥È¥Ð¥Ã¥¯¥â¡¼¥É
+* ¥é¥¤¥È¥Ð¥Ã¥¯¥â¡¼¥É (writeback mode)
data=writeback ¥â¡¼¥É¤Î¤È¤¡¢ext4 ¤Ï¥Ç¡¼¥¿¤òÁ´¤¯¥¸¥ã¡¼¥Ê¥ë¤·¤Þ¤»¤ó¡£
¤³¤ì¤Ï¡¢XFS, JFS, ReiserFS ¤Î¥Ç¥Õ¥©¥ë¥È¥â¡¼¥É (¥á¥¿¥Ç¡¼¥¿¥¸¥ã¡¼¥Ê¥ê¥ó¥°) ¤È
Ʊ¥ì¥Ù¥ë¤Î¥¸¥ã¡¼¥Ê¥ê¥ó¥°¤òÄ󶡤·¤Þ¤¹¡£
-¥¯¥é¥Ã¥·¥å + ¥ê¥«¥Ð¥ê ¤Ç¡¢¥¯¥é¥Ã¥·¥åľÁ°¤Ë½ñ¤¹þ¤Þ¤ì¤¿¥Õ¥¡¥¤¥ëÆâ¤ËÉÔÀµ¥Ç¡¼¥¿
-¤¬¸½¤ì¤ë¤«¤â¤·¤ì¤Þ¤»¤ó¡£Ä̾盧¤Î¥â¡¼¥É¤ÏºÇ¹â¤Î ext4 ¥Ñ¥Õ¥©¡¼¥Þ¥ó¥¹¤¬ÆÀ¤é¤ì¤Þ
-¤¹¡£
+¥¯¥é¥Ã¥·¥å + ¥ê¥«¥Ð¥ê ¤Ç¡¢¥¯¥é¥Ã¥·¥åľÁ°¤Ë½ñ¤¹þ¤Þ¤ì¤¿¥Õ¥¡¥¤¥ëÆâ¤ËÉÔÀµ¥Ç¡¼
+¥¿¤¬¸½¤ì¤ë¤«¤â¤·¤ì¤Þ¤»¤ó¡£Ä̾盧¤Î¥â¡¼¥É¤Ë¤è¤êºÇ¹â¤Î ext4 ¥Ñ¥Õ¥©¡¼¥Þ¥ó¥¹¤¬
+ÆÀ¤é¤ì¤Þ¤¹¡£
#* ordered mode
#In data=ordered mode, ext4 only officially journals metadata, but it logically
#groups metadata information related to data changes with the data blocks into a
#single unit called a transaction. When it's time to write the new metadata
#out to disk, the associated data blocks are written first. In general,
-#this mode performs slightly slower than writeback but significantly faster than
-journal mode.
-* ¥ª¡¼¥À¡¼¥É¥â¡¼¥É
+#this mode performs slightly slower than writeback but significantly faster
+#than journal mode.
+* ¥ª¡¼¥À¡¼¥É¥â¡¼¥É (ordered mode)
data=ordered ¥â¡¼¥É¤Î¤È¤¡¢ext4 ¤Ï¸ø¼°¤Ë¤Ï¥á¥¿¥Ç¡¼¥¿¤Î¤ß¤ò¥¸¥ã¡¼¥Ê¥ë¤·¤Þ¤¹
¤¬¡¢¤³¤ÎºÝ¤Ë¥á¥¿¥Ç¡¼¥¿¤È¥Ç¡¼¥¿¥Ö¥í¥Ã¥¯¤Ï¥È¥é¥ó¥¶¥¯¥·¥ç¥ó¤È¸Æ¤Ð¤ì¤ë 1 ¤Ä¤Îñ
°Ì¤Ë¡¢ÏÀÍýŪ¤Ë¤Þ¤È¤á¤é¤ì¤Æ¤¤¤Þ¤¹¡£¥Ç¥£¥¹¥¯¤Ë¿·¤·¤¤¥á¥¿¥Ç¡¼¥¿¤ò½ñ¤¹þ¤à»þ¤¬
#In the event of a crash, the journal can be replayed, bringing both data and
#metadata into a consistent state. This mode is the slowest except when data
#needs to be read from and written to disk at the same time where it
-#outperforms all others modes. Currently ext4 does not have delayed
-#allocation support if this data journalling mode is selected.
-* ¥¸¥ã¡¼¥Ê¥ë¥â¡¼¥É
+#outperforms all others modes. Enabling this mode will disable delayed
+#allocation and O_DIRECT support.
+* ¥¸¥ã¡¼¥Ê¥ë¥â¡¼¥É (journal mode)
data=journal ¥â¡¼¥É¤Ï¡¢¥Ç¡¼¥¿¤È¥á¥¿¥Ç¡¼¥¿¤Î´°Á´¤Ê¥¸¥ã¡¼¥Ê¥ê¥ó¥°¤òÈ÷¤¨¤Þ¤¹¡£
-¤¹¤Ù¤Æ¤Î¿·¤·¤¤¥Ç¡¼¥¿¤Ï¡¢Àè¤Ë¥¸¥ã¡¼¥Ê¥ë¤Ë½ñ¤¹þ¤Þ¤ì¡¢¤½¤Î¸å¤Ë½êÄê¤Î°ÌÃ֤ؽñ¤
-¤³¤Þ¤ì¤Þ¤¹¡£¥¯¥é¥Ã¥·¥å¤ÎºÝ¡¢¥¸¥ã¡¼¥Ê¥ë¤Ï¥ê¥×¥ì¥¤¤µ¤ì¡¢¥Ç¡¼¥¿¤È¥á¥¿¥Ç¡¼¥¿¤ÎξÊý
-¤ÏÌ·½â¤Î̵¤¤¾õÂ֤˲óÉü¤µ¤ì¤Þ¤¹¡£¤³¤Î¥â¡¼¥É¤Ï¤â¤Ã¤È¤âÃÙ¤¤¤Ç¤¹¤¬¡¢¥Ç¥£¥¹¥¯¤Ø¤Î
-¥Ç¡¼¥¿¤ÎÆɤߤÀ¤·¤È½ñ¤¹þ¤ß¤òƱ»þ¤Ë¹Ô¤¦É¬Íפ¬¤¢¤ë»þ¤Ï¡¢Â¾¤Î¥â¡¼¥É¤è¤ê¹âÀǽ¤Ç
-¤¹¡£¸½ºß¤Î ext4 ¤Ç¤Ï¡¢¤³¤Î¥Ç¡¼¥¿¥¸¥ã¡¼¥Ê¥ê¥ó¥°¥â¡¼¥É¤¬ÁªÂò¤µ¤ì¤Æ¤¤¤ë¤È¤¡¢
-Ãٱ䥢¥í¥±¡¼¥·¥ç¥ó¤Ï¥µ¥Ý¡¼¥È¤µ¤ì¤Æ¤¤¤Þ¤»¤ó¡£
+¤¹¤Ù¤Æ¤Î¿·¤·¤¤¥Ç¡¼¥¿¤Ï¡¢Àè¤Ë¥¸¥ã¡¼¥Ê¥ë¤Ë½ñ¤¹þ¤Þ¤ì¡¢¤½¤Î¸å¤Ë½êÄê¤Î°ÌÃ֤ؽñ
+¤¤³¤Þ¤ì¤Þ¤¹¡£¥¯¥é¥Ã¥·¥å¤ÎºÝ¡¢¥¸¥ã¡¼¥Ê¥ë¤Ï¥ê¥×¥ì¥¤¤µ¤ì¡¢¥Ç¡¼¥¿¤È¥á¥¿¥Ç¡¼¥¿
+¤ÎξÊý¤ÏÌ·½â¤Î̵¤¤¾õÂ֤˲óÉü¤µ¤ì¤Þ¤¹¡£¤³¤Î¥â¡¼¥É¤ÏÄ̾ï¤Ï¤â¤Ã¤È¤âÃÙ¤¤¤â¤Î¤Ç
+¤¹¤¬¡¢¥Ç¥£¥¹¥¯¤Ø¤Î¥Ç¡¼¥¿¤ÎÆɤߤÀ¤·¤È½ñ¤¹þ¤ß¤òƱ»þ¤Ë¹Ô¤¦É¬Íפ¬¤¢¤ë»þ¤Ï¡¢Â¾
+¤Î¥â¡¼¥É¤è¤ê¹âÀǽ¤Ç¤¹¡£¤³¤Î¥â¡¼¥É¤ò͸ú¤Ë¤·¤¿¾ì¹ç¡¢Ãٱ䥢¥í¥±¡¼¥·¥ç¥ó¤È
+O_DIRECT ¥µ¥Ý¡¼¥È¤Ï̵¸ú¤Ë¤Ê¤ê¤Þ¤¹¡£
+
+
+#/proc entries
+#=============
+/proc ¥¨¥ó¥È¥ê
+==============
+
+#Information about mounted ext4 file systems can be found in
+#/proc/fs/ext4. Each mounted filesystem will have a directory in
+#/proc/fs/ext4 based on its device name (i.e., /proc/fs/ext4/hdc or
+#/proc/fs/ext4/dm-0). The files in each per-device directory are shown
+#in table below.
+¥Þ¥¦¥ó¥È¤µ¤ì¤Æ¤¤¤ë ext4 ¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Î¾ðÊó¤Ï /proc/fs/ext4 ¤«¤é¼èÆÀ¤Ç
+¤¤Þ¤¹¡£¥Þ¥¦¥ó¥È¤µ¤ì¤Æ¤¤¤ë¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Î³Æ¡¹¤ËÂбþ¤·¤¿¡¢¥Ç¥Ð¥¤¥¹Ì¾¤ò¸µ
+¤Ë¤·¤¿Ì¾¾Î¤Î¥Ç¥£¥ì¥¯¥È¥ê¤¬ /proc/fs/ext4 °Ê²¼¤ËºîÀ®¤µ¤ì¤Þ¤¹ (Î㤨¤Ð
+/proc/fs/ext4/hdc ¤ä /proc/fs/ext4/dm-0)¡£³Æ¥Ç¥Ð¥¤¥¹¤´¤È¤Î¥Ç¥£¥ì¥¯¥È¥êÆâ¤Î
+¥Õ¥¡¥¤¥ë¤Ï°Ê²¼¤Î¥Æ¡¼¥Ö¥ë¤Î¤È¤ª¤ê¤Ç¤¹¡£
+
+#Files in /proc/fs/ext4/<devname>
+/proc/fs/ext4/<devname> ¤Î¥Õ¥¡¥¤¥ë
+..............................................................................
+# File Content
+# mb_groups details of multiblock allocator buddy cache of free blocks
+ ¥Õ¥¡¥¤¥ë ÆâÍÆ
+ mb_groups ¥Õ¥ê¡¼¥Ö¥í¥Ã¥¯¤Î buddy ¥¥ã¥Ã¥·¥å¤Î¥Þ¥ë¥Á¥Ö¥í¥Ã¥¯¥¢¥í¥±
+ ¡¼¥¿¤Î¾ÜºÙ¾ðÊó
+..............................................................................
+
+#/sys entries
+#============
+/sys ¥¨¥ó¥È¥ê
+=============
+
+#Information about mounted ext4 file systems can be found in
+#/sys/fs/ext4. Each mounted filesystem will have a directory in
+#/sys/fs/ext4 based on its device name (i.e., /sys/fs/ext4/hdc or
+#/sys/fs/ext4/dm-0). The files in each per-device directory are shown
+#in table below.
+¥Þ¥¦¥ó¥È¤µ¤ì¤¿ ext4 ¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Î¾ðÊó¤Ï /sys/fs/ext4 ¤«¤é¼èÆÀ¤Ç¤¤Þ¤¹¡£
+¥Þ¥¦¥ó¥È¤µ¤ì¤Æ¤¤¤ë¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Î³Æ¡¹¤ËÂбþ¤·¤Æ¡¢¥Ç¥Ð¥¤¥¹Ì¾¤ò¸µ¤Ë¤·¤¿Ì¾
+¾Î¤Î¥Ç¥£¥ì¥¯¥È¥ê¤¬ /sys/fs/ext4 °Ê²¼¤ËºîÀ®¤µ¤ì¤Þ¤¹ (Î㤨¤Ð
+/sys/fs/ext4/hdc ¤ä /sys/fs/ext4/dm-0)¡£³Æ¥Ç¥Ð¥¤¥¹¤´¤È¤Î¥Ç¥£¥ì¥¯¥È¥êÆâ¤Î
+¥Õ¥¡¥¤¥ë¤Ï°Ê²¼¤Î¥Æ¡¼¥Ö¥ë¤Î¤È¤ª¤ê¤Ç¤¹¡£
+
+
+#Files in /sys/fs/ext4/<devname>
+#(see also Documentation/ABI/testing/sysfs-fs-ext4)
+/sys/fs/ext4/<devname> ¤Î¥Õ¥¡¥¤¥ë
+ (Documentation/ABI/testing/sysfs-fs-ext4 ¤â¸«¤Æ¤¯¤À¤µ¤¤)
+..............................................................................
+# File Content
+ ¥Õ¥¡¥¤¥ë ÆâÍÆ
+
+# delayed_allocation_blocks This file is read-only and shows the number of
+# blocks that are dirty in the page cache, but
+# which do not have their location in the
+# filesystem allocated yet.
+ delayed_allocation_blocks ¤³¤Î¥Õ¥¡¥¤¥ë¤Ï¥ê¡¼¥É¥ª¥ó¥ê¡¼¤Ç¡¢¥Ú¡¼¥¸¥¥ã¥Ã
+ ¥·¥åÆâ¤Î¥À¡¼¥Æ¥£¤Ç¡¢¤«¤Ä¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥àÆâ¤Ë
+ ¤Þ¤ÀÎΰ褬³ä¤êÅö¤Æ¤é¤ì¤Æ¤¤¤Ê¤¤¥Ú¡¼¥¸¤Î¿ô¤ò¼¨
+ ¤·¤Þ¤¹¡£
+
+# inode_goal Tuning parameter which (if non-zero) controls
+# the goal inode used by the inode allocator in
+# preference to all other allocation heuristics.
+# This is intended for debugging use only, and
+# should be 0 on production systems.
+ inode_goal ¥Á¥å¡¼¥Ë¥ó¥°¥Ñ¥é¥á¡¼¥¿¤Ç¤¢¤ê¡¢inode ¥¢¥í¥±¡¼
+ ¥¿¤ÇÍѤ¤¤ë goal inode ¤ÎµóÆ°¤ò¾¤Î¥¢¥í¥±¡¼¥·
+ ¥ç¥óÀïά¤ËÍ¥À褷¤Æ (0 °Ê³°¤Î¾ì¹ç¤Ë) À©¸æ¤¹¤ë
+ ¤¿¤á¤Î¤â¤Î¤Ç¤¹¡£
+ ¤³¤ì¤Ï¥Ç¥Ð¥Ã¥°¤Î¤ß¤ÇÍøÍѤ¹¤ë¤³¤È¤ò°Õ¿Þ¤·¤Æ¤ª
+ ¤ê¡¢Ä̾ﱿÍÑ»þ¤Ï 0 ¤Ë¤·¤Æ¤ª¤¯¤Ù¤¤Ç¤¹¡£
+
+# inode_readahead_blks Tuning parameter which controls the maximum
+# number of inode table blocks that ext4's inode
+# table readahead algorithm will pre-read into
+# the buffer cache
+ inode_readahead_blks ¥Á¥å¡¼¥Ë¥ó¥°¥Ñ¥é¥á¡¼¥¿¤Ç¤¢¤ê¡¢ext4 ¤Î inode
+ ¥Æ¡¼¥Ö¥ëÀèÆɤߥ¢¥ë¥´¥ê¥º¥à¤¬¥Ð¥Ã¥Õ¥¡¥¥ã¥Ã¥·
+ ¥å¤ËÀèÆɤߤ¹¤ë inode ¥Æ¡¼¥Ö¥ë¤Î¥Ö¥í¥Ã¥¯¿ô¤ò
+ »ØÄꤷ¤Þ¤¹¡£
+
+# lifetime_write_kbytes This file is read-only and shows the number of
+# kilobytes of data that have been written to this
+# filesystem since it was created.
+ lifetime_write_kbytes ¤³¤Î¥Õ¥¡¥¤¥ë¤Ï¥ê¡¼¥É¥ª¥ó¥ê¡¼¤Ç¡¢ºîÀ®¤µ¤ì¤Æ¤«
+ ¤é°Ê¹ß¤³¤Î¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Ë½ñ¤¤³¤Þ¤ì¤¿¥Ç¡¼¥¿¤ò
+ ¥¥í¥Ð¥¤¥Èñ°Ì¤Ç¼¨¤·¤Þ¤¹¡£
+
+# max_writeback_mb_bump The maximum number of megabytes the writeback
+# code will try to write out before move on to
+# another inode.
+ max_writeback_mb_bump ¥é¥¤¥È¥Ð¥Ã¥¯¥³¡¼¥É¤¬¼¡¤Î inode ¤Ë¿Ê¤àÁ°¤Ë½ñ
+ ¤¤³¤ß¤ò»î¤ß¤ë¥µ¥¤¥º¤ÎºÇÂçÃͤò¥á¥¬¥Ð¥¤¥Èñ°Ì
+ ¤Ç»ØÄꤷ¤Þ¤¹¡£
+
+# mb_group_prealloc The multiblock allocator will round up allocation
+# requests to a multiple of this tuning parameter if
+# the stripe size is not set in the ext4 superblock
+ mb_group_prealloc ¥Þ¥ë¥Á¥Ö¥í¥Ã¥¯¥¢¥í¥±¡¼¥¿¤Ï¡¢ext4 ¥¹¡¼¥Ñ¡¼¥Ö
+ ¥í¥Ã¥¯Æâ¤Ë¥¹¥È¥é¥¤¥×¥µ¥¤¥º¤¬»ØÄꤵ¤ì¤Æ¤¤¤Ê¤¤
+ ¾ì¹ç¡¢¥¢¥í¥±¡¼¥·¥ç¥óÍ×µá¤ò¤³¤Î¥Á¥å¡¼¥Ë¥ó¥°¥Ñ
+ ¥é¥á¡¼¥¿¤ÎÀ°¿ôÇܤËÀÚ¤ê¾å¤²¤Þ¤¹¡£
+
+# mb_max_to_scan The maximum number of extents the multiblock
+# allocator will search to find the best extent
+ mb_max_to_scan ¥Þ¥ë¥Á¥Ö¥í¥Ã¥¯¥¢¥í¥±¡¼¥¿¤¬ºÇŬ¤Ê¥¨¥¯¥¹¥Æ¥ó¥È
+ ¤òõ¤¹ºÝ¤Ëõº÷¤¹¤ë¥¨¥¯¥¹¥Æ¥ó¥È¤ÎºÇÂçÃͤò»ØÄê
+ ¤·¤Þ¤¹¡£
+
+# mb_min_to_scan The minimum number of extents the multiblock
+# allocator will search to find the best extent
+ mb_min_to_scan ¥Þ¥ë¥Á¥Ö¥í¥Ã¥¯¥¢¥í¥±¡¼¥¿¤¬ºÇŬ¤Ê¥¨¥¯¥¹¥Æ¥ó¥È
+ ¤òõ¤¹ºÝ¤Ëõº÷¤¹¤ë¥¨¥¯¥¹¥Æ¥ó¥È¤ÎºÇ¾®Ãͤò»ØÄê
+ ¤·¤Þ¤¹¡£
+
+# mb_order2_req Tuning parameter which controls the minimum size
+# for requests (as a power of 2) where the buddy
+# cache is used
+ mb_order2_req buddy ¥¥ã¥Ã¥·¥å»ÈÍÑ»þ¤Ë¥ê¥¯¥¨¥¹¥È¤ÎºÇ¾®¥µ¥¤
+ ¥º¤ò 2 ¤Î¤Ù¤¾è¤Ç»ØÄꤹ¤ë¥Á¥å¡¼¥Ë¥ó¥°¥Ñ¥é¥á¡¼
+ ¥¿¤Ç¤¹¡£
+
+# mb_stats Controls whether the multiblock allocator should
+# collect statistics, which are shown during the
+# unmount. 1 means to collect statistics, 0 means
+# not to collect statistics
+ mb_stats ¥Þ¥ë¥Á¥Ö¥í¥Ã¥¯¥¢¥í¥±¡¼¥¿¤¬ unmount »þ¤Ëɽ¼¨¤¹
+ ¤ë¤¿¤á¤ÎÅý·×¾ðÊó¤ò½¸¤á¤ë¤«Èݤ«¤òÀ©¸æ¤·¤Þ¤¹¡£
+ 1 ¤ÏÅý·×¾ðÊó¤ò½¸¤á¤ë¤³¤È¤ò¡¢0 ¤Ï½¸¤á¤Ê¤¤¤³¤È
+ ¤ò°ÕÌ£¤·¤Þ¤¹¡£
+
+# mb_stream_req Files which have fewer blocks than this tunable
+# parameter will have their blocks allocated out
+# of a block group specific preallocation pool, so
+# that small files are packed closely together.
+# Each large file will have its blocks allocated
+# out of its own unique preallocation pool.
+ mb_stream_req ¤³¤ì¤Ï¥Á¥å¡¼¥Ë¥ó¥°¥Ñ¥é¥á¡¼¥¿¤Ç¤¢¤ê¡¢¤³¤Î¥Ñ¥é
+ ¥á¡¼¥¿°Ê²¼¤Î¥Ö¥í¥Ã¥¯¿ô¤Î³ä¤êÅö¤Æ¤Î¾ì¹ç¤Ë¤Ï¡¢
+ ¥Ö¥í¥Ã¥¯¥°¥ë¡¼¥×Ê̤λöÁ°³ä¤êÅö¤Æ¥×¡¼¥ë¤«¤é¥Ö
+ ¥í¥Ã¥¯¤ò³ä¤êÅö¤Æ¤ë¤è¤¦¤Ë¤·¡¢¾®¤µ¤¤¥Õ¥¡¥¤¥ë¤¬
+ ¶á¤¯¤Ë¥Ñ¥Ã¥¯¤µ¤ì¤Æ½¸¤á¤é¤ì¤ë¤è¤¦¤Ë¤·¤Þ¤¹¡£
+ Â礤ʥե¡¥¤¥ë¤Ï¡¢Â礤ʥե¡¥¤¥ëÍѤλöÁ°³ä¤ê
+ Åö¤Æ¥×¡¼¥ë¤«¤é¥Ö¥í¥Ã¥¯¤¬³ä¤êÅö¤Æ¤é¤ì¤Þ¤¹¡£
+
+# session_write_kbytes This file is read-only and shows the number of
+# kilobytes of data that have been written to this
+# filesystem since it was mounted.
+ session_write_kbytes ¤³¤Î¥Õ¥¡¥¤¥ë¤Ï¥ê¡¼¥É¥ª¥ó¥ê¡¼¤Ç¡¢¥Þ¥¦¥ó¥È¤µ¤ì
+ ¤Æ¤«¤é¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Ë½ñ¤¤³¤Þ¤ì¤¿¥Ç¡¼¥¿¤ò
+ ¥¥í¥Ð¥¤¥Èñ°Ì¤Ç¼¨¤·¤Þ¤¹¡£
+..............................................................................
+
+Ioctls
+======
+
+#There is some Ext4 specific functionality which can be accessed by applications
+#through the system call interfaces. The list of all Ext4 specific ioctls are
+#shown in the table below.
+¥·¥¹¥Æ¥à¥³¡¼¥ë¥¤¥ó¥¿¡¼¥Õ¥§¡¼¥¹¤Ë¤è¤ê¥¢¥×¥ê¥±¡¼¥·¥ç¥ó¤«¤é¥¢¥¯¥»¥¹²Äǽ¤Ê ext4
+¸Çͤε¡Ç½¤¬¤¤¤¯¤Ä¤«¤¢¤ê¤Þ¤¹¡£ext4 ¸ÇͤΠioctl ¤Î°ìÍ÷¤ò°Ê²¼¤Îɽ¤Ë¼¨¤·¤Þ¤¹¡£
+
+#Table of Ext4 specific ioctls
+ext4 ¸ÇͤΠioctl ¤Îɽ
+..............................................................................
+# Ioctl Description
+ Ioctl ÀâÌÀ
+# EXT4_IOC_GETFLAGS Get additional attributes associated with inode.
+# The ioctl argument is an integer bitfield, with
+# bit values described in ext4.h. This ioctl is an
+# alias for FS_IOC_GETFLAGS.
+ EXT4_IOC_GETFLAGS inode ¤Ë´Ø·¸¤¹¤ëÄɲ墥ȥê¥Ó¥å¡¼¥È¤ò¼èÆÀ¤·¤Þ¤¹¡£
+ ¤³¤Î ioctl ¤Î°ú¿ô¤Ï¥Ó¥Ã¥È¥Õ¥£¡¼¥ë¥É¤Ç¡¢³Æ bit
+ ¤Î°ÕÌ£¤Ï ext4.h ¤ËµºÜ¤µ¤ì¤Æ¤¤¤Þ¤¹¡£¤³¤Î ioctl
+ ¤Ï FS_IOC_GETFLAG ¤ÎÊÌ̾¤Ë¤Ê¤ê¤Þ¤¹¡£
+
+# EXT4_IOC_SETFLAGS Set additional attributes associated with inode.
+# The ioctl argument is an integer bitfield, with
+# bit values described in ext4.h. This ioctl is an
+# alias for FS_IOC_SETFLAGS.
+ EXT4_IOC_SETFLAGS inode ¤Ë´Ø·¸¤¹¤ëÄɲ墥ȥê¥Ó¥å¡¼¥È¤òÀßÄꤷ¤Þ¤¹¡£
+ ¤³¤Î ioctl ¤Î°ú¿ô¤Ï¥Ó¥Ã¥È¥Õ¥£¡¼¥ë¥É¤Ç¡¢³Æ bit
+ ¤Î°ÕÌ£¤Ï ext4.h ¤ËµºÜ¤µ¤ì¤Æ¤¤¤Þ¤¹¡£¤³¤Î ioctl
+ ¤Ï FS_IOC_SETFLAG ¤ÎÊÌ̾¤Ë¤Ê¤ê¤Þ¤¹¡£
+
+ EXT4_IOC_GETVERSION
+ EXT4_IOC_GETVERSION_OLD
+# Get the inode i_generation number stored for
+# each inode. The i_generation number is normally
+# changed only when new inode is created and it is
+# particularly useful for network filesystems. The
+# '_OLD' version of this ioctl is an alias for
+# FS_IOC_GETVERSION.
+ ³Æ inode ¤Ë³ÊǼ¤µ¤ì¤Æ¤¤¤ë inode ¤Î
+ i_generation ÈÖ¹æ¤ò¼èÆÀ¤·¤Þ¤¹¡£i_generation
+ ÈÖ¹æ¤ÏÄ̾￷¤·¤¤ inode ¤¬ºîÀ®¤µ¤ì¤ë¾ì¹ç¤Ë¤Î¤ß
+ Êѹ¹¤µ¤ì¡¢¥Í¥Ã¥È¥ï¡¼¥¯¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤ÇÆäËÍÍѤǤ¹¡£
+ _OLD ¤ÎÉÕ¤¯ÈǤΠioctl ¤Ï FS_IOC_GETVERSION ¤Î
+ ÊÌ̾¤Ç¤¹¡£
+
+ EXT4_IOC_SETVERSION
+ EXT4_IOC_SETVERSION_OLD
+# Set the inode i_generation number stored for
+# each inode. The '_OLD' version of this ioctl
+# is an alias for FS_IOC_SETVERSION.
+ ³Æ inode ¤Ë³ÊǼ¤µ¤ì¤Æ¤¤¤ë inode ¤Î
+ i_generation ÈÖ¹æ¤òÀßÄꤷ¤Þ¤¹¡£
+ _OLD ¤ÎÉÕ¤¯ÈǤΠioctl ¤Ï FS_IOC_SETVERSION ¤Î
+ ÊÌ̾¤Ç¤¹¡£
+
+# EXT4_IOC_GROUP_EXTEND This ioctl has the same purpose as the resize
+# mount option. It allows to resize filesystem
+# to the end of the last existing block group,
+# further resize has to be done with resize2fs,
+# either online, or offline. The argument points
+# to the unsigned logn number representing the
+# filesystem new block count.
+ EXT4_IOC_GROUP_EXTEND ¤³¤Î ioctl ¤Ï resize mount ¥ª¥×¥·¥ç¥ó¤ÈƱ¤¸ÌÜ
+ Ū¤ò»ý¤Á¤Þ¤¹¡£¤³¤ì¤Ë¤è¤ê¡¢ºÇ½ª¤Î»ÈÍѺѤߤΥÖ
+ ¥í¥Ã¥¯¥°¥ë¡¼¥×¤Ø¤Î¥ê¥µ¥¤¥º¤¬²Äǽ¤Ë¤Ê¤ê¤Þ¤¹¡£
+ ¤³¤ì°Ê¾å¤Î¥ê¥µ¥¤¥º¤Ï¡¢resize2fs¤òÍѤ¤¤Æ¹Ô¤¦É¬
+ Íפ¬¤¢¤ê¤Þ¤¹¡£°ú¿ô¤Ï¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Î¿·¤·¤¤
+ ¥Ö¥í¥Ã¥¯¿ô¤ò¼¨¤¹ÌµÉä¹æ long ·¿À°¿ô¤ò»Ø¤·¤Þ¤¹¡£
+
+# EXT4_IOC_MOVE_EXT Move the block extents from orig_fd (the one
+# this ioctl is pointing to) to the donor_fd (the
+# one specified in move_extent structure passed
+# as an argument to this ioctl). Then, exchange
+# inode metadata between orig_fd and donor_fd.
+# This is especially useful for online
+# defragmentation, because the allocator has the
+# opportunity to allocate moved blocks better,
+# ideally into one contiguous extent.
+ EXT4_IOC_MOVE_EXT orig_fd (ioctl ¤Î»Ø¤¹°ÌÃÖ) ¤Î¥Ö¥í¥Ã¥¯¥¨¥¯¥¹¥Æ
+ ¥ó¥È¤ò doner_fd (ioctl ¤Ø¤Î°ú¿ô¤È¤·¤ÆÍ¿¤¨¤é¤ì
+ ¤ë move_extent ¹½Â¤ÂΤǻØÄꤵ¤ì¤¿°ÌÃÖ) ¤Ë°ÜÆ°
+ ¤·¡¢orig_fd ¤È doner_fd ¤Î inode ¥á¥¿¥Ç¡¼¥¿¤ò
+ ¸ò´¹¤·¤Þ¤¹¡£¤³¤Îµ¡Ç½¤Ï¡¢°ÜÆ°¤µ¤ì¤ë¥Ö¥í¥Ã¥¯¤Î³ä
+ ¤êÅö¤Æ¤ò²þÁ±¤Ç¤¤ë (Î㤨¤Ð¤Ò¤È¤Ä¤ÎÎÙÀܤ¹¤ë¥¨¥¯
+ ¥¹¥Æ¥ó¥È¤Ë³ä¤êÅö¤Æ¤é¤ì¤ì¤ÐÍýÁÛŪ¤Ç¤¹) ²ÄǽÀ¤¬
+ ¤¢¤ë¤¿¤á¡¢Æä˥ª¥ó¥é¥¤¥ó¥Ç¥Õ¥é¥°¤ÇÊØÍø¤Ç¤¹¡£
+
+# EXT4_IOC_GROUP_ADD Add a new group descriptor to an existing or
+# new group descriptor block. The new group
+# descriptor is described by ext4_new_group_input
+# structure, which is passed as an argument to
+# this ioctl. This is especially useful in
+# conjunction with EXT4_IOC_GROUP_EXTEND,
+# which allows online resize of the filesystem
+# to the end of the last existing block group.
+# Those two ioctls combined is used in userspace
+# online resize tool (e.g. resize2fs).
+ EXT4_IOC_GROUP_ADD ´û¸¤Þ¤¿¤Ï¿·µ¬¤Î¥°¥ë¡¼¥×¥Ç¥£¥¹¥¯¥ê¥×¥¿¥Ö¥í¥Ã¥¯
+ ¤Ë¿·¤·¤¤¥°¥ë¡¼¥×¥Ç¥£¥¹¥¯¥ê¥×¥¿¤òÄɲä·¤Þ¤¹¡£¿·
+ ¤·¤¤¥°¥ë¡¼¥×¥Ç¥£¥¹¥¯¥ê¥×¥¿¤Ï¡¢¤³¤Î ioctl ¤Î°ú
+ ¿ô¤È¤·¤ÆÅϤµ¤ì¤ë ext4_new_group_input ¹½Â¤ÂΤË
+ µºÜ¤µ¤ì¤Þ¤¹¡£
+ ¤³¤Îµ¡Ç½¤ÏºÇ½ª¤Î»ÈÍѺѤߤΥ֥í¥Ã¥¯¥°¥ë¡¼¥×¤Ø¤Î
+ ¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Î¥ª¥ó¥é¥¤¥ó¥ê¥µ¥¤¥º¤ò¹Ô¤¦
+ EXT4_IOC_GROUP_EXTEND µ¡Ç½¤ÈÁȤ߹ç¤ï¤»¤Æ»È¤¦¤È
+ ÊØÍø¤Ç¤¹¡£¤³¤Î 2 ¤Ä¤Î ioctl ¤Ï¥æ¡¼¥¶¶õ´Ö¥ª¥ó¥é
+ ¥¤¥ó¥ê¥µ¥¤¥º¥Ä¡¼¥ë (¤Ä¤Þ¤ê resize2fs) ¤ÇÁȤ߹ç
+ ¤ï¤»¤Æ»È¤ï¤ì¤Æ¤¤¤Þ¤¹¡£
+
+# EXT4_IOC_MIGRATE This ioctl operates on the filesystem itself.
+# It converts (migrates) ext3 indirect block mapped
+# inode to ext4 extent mapped inode by walking
+# through indirect block mapping of the original
+# inode and converting contiguous block ranges
+# into ext4 extents of the temporary inode. Then,
+# inodes are swapped. This ioctl might help, when
+# migrating from ext3 to ext4 filesystem, however
+# suggestion is to create fresh ext4 filesystem
+# and copy data from the backup. Note, that
+# filesystem has to support extents for this ioctl
+# to work.
+ EXT4_IOC_MIGRATE ¤³¤Î ioctl ¤Ï¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¼«ÂΤòÁàºî¤·¤Þ¤¹¡£
+ ¤³¤ì¤Ï¡¢ext3 ¤Î´ÖÀÜ¥Ö¥í¥Ã¥¯¥Þ¥Ã¥×¤µ¤ì¤¿ inode
+ ¤ò ext4 ¤Î¥¨¥¯¥¹¥Æ¥ó¥È¥Þ¥Ã¥×¤µ¤ì¤¿ inode ¤Ë¡¢
+ ¸µ¤Î inode ¤Î´ÖÀÜ¥Ö¥í¥Ã¥¯¥Þ¥Ã¥×¤ò¼ê·«¤Ã¤ÆÎÙÀÜ
+ ¥Ö¥í¥Ã¥¯ÈϰϤËÊÑ´¹¤·¤Æ¹¹¤Ë°ì»þ inode ¤Î ext4
+ ¥¨¥¯¥¹¥Æ¥ó¥È¤ËÊÑ´¹¡¢¤½¤Î¤¢¤È inode ¤ò¸ò´¹¤¹¤ë
+ ¤³¤È¤Ë¤è¤êÊÑ´¹¤·¤Æ°Ü¹Ô¤·¤Þ¤¹¡£¤³¤Îµ¡Ç½¤Ï ext3
+ ¤«¤é ext4 ¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Ø¤Î°Ü¹Ô»þ¤ËÍøÍѲÄǽ
+ ¤Ç¤¹¤¬¡¢ext4 ¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤ò¿·µ¬¤Ëºî¤Ã¤Æ¤½
+ ¤³¤Ë¥Ð¥Ã¥¯¥¢¥Ã¥×¤«¤é¥Ç¡¼¥¿¤ò¥³¥Ô¡¼¤¹¤ëÊý¤¬¤è¤ê
+ Îɤ¤¤ä¤êÊý¤Ç¤¹¡£¤³¤Î ioctl ¤ÎÆ°ºî¤Î¤¿¤á¤Ë¤Ï¥Õ
+ ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤¬¥¨¥¯¥¹¥Æ¥ó¥È¤ò¥µ¥Ý¡¼¥È¤·¤Æ¤¤¤ë
+ ɬÍפ¬¤¢¤ë¤³¤È¤Ëα°Õ¤¯¤À¤µ¤¤¡£
+
+# EXT4_IOC_ALLOC_DA_BLKS Force all of the delay allocated blocks to be
+# allocated to preserve application-expected ext3
+# behaviour. Note that this will also start
+# triggering a write of the data blocks, but this
+# behaviour may change in the future as it is
+# not necessary and has been done this way only
+# for sake of simplicity.
+ EXT4_IOC_ALLOC_DA_BLKS ÃÙ±ä³ä¤êÅö¤ÆÂоݤΥ֥í¥Ã¥¯¤ò¶¯À©Åª¤ËÁ´¤Æ³ä¤êÅö
+ ¤Æ¤ë¤³¤È¤Ë¤è¤ê¡¢¥¢¥×¥ê¥±¡¼¥·¥ç¥ó¤«¤é¸«¤Æ ext3
+ ¤ÎµóÆ°¤ÈƱ¤¸¤Ë¤Ê¤ë¤è¤¦¤Ë¤·¤Þ¤¹¡£¤³¤Îµ¡Ç½¤Ë¤è¤ê
+ ¸½ºß¤Î¼ÂÁõ¤Ç¤Ï¥Ç¡¼¥¿¥Ö¥í¥Ã¥¯¤Î½ñ¤¹þ¤ß¤¬»Ï¤Þ¤ë
+ ¤³¤È¤ËÃí°Õ¤·¤Æ¤¯¤À¤µ¤¤¡£¤¿¤À¤·¡¢¤³¤Î¿¶¤ëÉñ¤¤¤Ï
+ ɬÍפʤâ¤Î¤Ç¤Ï¤Ê¤¯¡¢Ã±½ã²½¤Î¤¿¤á¤Ë¤ª¤³¤Ê¤ï¤ì¤Æ
+ ¤¤¤ë¤â¤Î¤Ç¤¢¤ë¤¿¤á¡¢¾ÍèÊѹ¹¤µ¤ì¤ë²ÄǽÀ¤Ï¤¢¤ê
+ ¤Þ¤¹¡£
+
+# EXT4_IOC_RESIZE_FS Resize the filesystem to a new size. The number
+# of blocks of resized filesystem is passed in via
+# 64 bit integer argument. The kernel allocates
+# bitmaps and inode table, the userspace tool thus
+# just passes the new number of blocks.
+ EXT4_IOC_RESIZE_FS ¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤ò¿·¤·¤¤¥µ¥¤¥º¤Ë¥ê¥µ¥¤¥º¤·¤Þ
+ ¤¹¡£¥ê¥µ¥¤¥º¸å¤Î¥Õ¥¡¥¤¥ë¥·¥¹¥Æ¥à¤Î¥Ö¥í¥Ã¥¯¿ô
+ ¤¬ 64-bit À°¿ôÃͤΰú¿ô¤È¤·¤ÆÅϤµ¤ì¤Þ¤¹¡£¥«¡¼
+ ¥Í¥ë¤¬¥Ó¥Ã¥È¥Þ¥Ã¥×¤È inode ¥Æ¡¼¥Ö¥ë¤ò³ä¤êÅö¤Æ
+ ¤ë¤¿¤á¡¢¥æ¡¼¥¶¶õ´Ö¤Î¥Ä¡¼¥ë¤Ï¿·¤·¤¤¥Ö¥í¥Ã¥¯¤Î
+ ¿ô¤òñ¤ËÅϤ¹¤À¤±¤Ç¤¹¡£
+..............................................................................
#References
#==========
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