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@@ -2,19 +2,24 @@
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Ext4 Filesystem
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Ext4 Filesystem
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===============
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===============
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-This is a development version of the ext4 filesystem, an advanced level
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-of the ext3 filesystem which incorporates scalability and reliability
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-enhancements for supporting large filesystems (64 bit) in keeping with
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-increasing disk capacities and state-of-the-art feature requirements.
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+Ext4 is an an advanced level of the ext3 filesystem which incorporates
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+scalability and reliability enhancements for supporting large filesystems
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+(64 bit) in keeping with increasing disk capacities and state-of-the-art
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+feature requirements.
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-Mailing list: linux-ext4@vger.kernel.org
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+Mailing list: linux-ext4@vger.kernel.org
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+Web site: http://ext4.wiki.kernel.org
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1. Quick usage instructions:
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1. Quick usage instructions:
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===========================
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===========================
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+Note: More extensive information for getting started with ext4 can be
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+ found at the ext4 wiki site at the URL:
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+ http://ext4.wiki.kernel.org/index.php/Ext4_Howto
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+
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- Compile and install the latest version of e2fsprogs (as of this
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- Compile and install the latest version of e2fsprogs (as of this
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- writing version 1.41) from:
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+ writing version 1.41.3) from:
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http://sourceforge.net/project/showfiles.php?group_id=2406
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http://sourceforge.net/project/showfiles.php?group_id=2406
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@@ -36,11 +41,9 @@ Mailing list: linux-ext4@vger.kernel.org
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# mke2fs -t ext4 /dev/hda1
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# mke2fs -t ext4 /dev/hda1
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- Or configure an existing ext3 filesystem to support extents and set
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- the test_fs flag to indicate that it's ok for an in-development
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- filesystem to touch this filesystem:
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+ Or to configure an existing ext3 filesystem to support extents:
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- # tune2fs -O extents -E test_fs /dev/hda1
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+ # tune2fs -O extents /dev/hda1
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If the filesystem was created with 128 byte inodes, it can be
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If the filesystem was created with 128 byte inodes, it can be
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converted to use 256 byte for greater efficiency via:
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converted to use 256 byte for greater efficiency via:
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@@ -104,8 +107,8 @@ exist yet so I'm not sure they're in the near-term roadmap.
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The big performance win will come with mballoc, delalloc and flex_bg
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The big performance win will come with mballoc, delalloc and flex_bg
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grouping of bitmaps and inode tables. Some test results available here:
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grouping of bitmaps and inode tables. Some test results available here:
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- - http://www.bullopensource.org/ext4/20080530/ffsb-write-2.6.26-rc2.html
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- - http://www.bullopensource.org/ext4/20080530/ffsb-readwrite-2.6.26-rc2.html
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+ - http://www.bullopensource.org/ext4/20080818-ffsb/ffsb-write-2.6.27-rc1.html
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+ - http://www.bullopensource.org/ext4/20080818-ffsb/ffsb-readwrite-2.6.27-rc1.html
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3. Options
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3. Options
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==========
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==========
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@@ -214,9 +217,6 @@ noreservation
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bsddf (*) Make 'df' act like BSD.
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bsddf (*) Make 'df' act like BSD.
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minixdf Make 'df' act like Minix.
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minixdf Make 'df' act like Minix.
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-check=none Don't do extra checking of bitmaps on mount.
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-nocheck
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-
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debug Extra debugging information is sent to syslog.
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debug Extra debugging information is sent to syslog.
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errors=remount-ro(*) Remount the filesystem read-only on an error.
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errors=remount-ro(*) Remount the filesystem read-only on an error.
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@@ -253,8 +253,6 @@ nobh (a) cache disk block mapping information
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"nobh" option tries to avoid associating buffer
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"nobh" option tries to avoid associating buffer
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heads (supported only for "writeback" mode).
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heads (supported only for "writeback" mode).
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-mballoc (*) Use the multiple block allocator for block allocation
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-nomballoc disabled multiple block allocator for block allocation.
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stripe=n Number of filesystem blocks that mballoc will try
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stripe=n Number of filesystem blocks that mballoc will try
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to use for allocation size and alignment. For RAID5/6
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to use for allocation size and alignment. For RAID5/6
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systems this should be the number of data
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systems this should be the number of data
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