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@@ -29,23 +29,25 @@ config EXT3_FS
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module will be called ext3.
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config EXT3_DEFAULTS_TO_ORDERED
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- bool "Default to 'data=ordered' in ext3 (legacy option)"
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+ bool "Default to 'data=ordered' in ext3"
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depends on EXT3_FS
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help
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- If a filesystem does not explicitly specify a data ordering
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- mode, and the journal capability allowed it, ext3 used to
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- historically default to 'data=ordered'.
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-
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- That was a rather unfortunate choice, because it leads to all
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- kinds of latency problems, and the 'data=writeback' mode is more
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- appropriate these days.
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-
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- You should probably always answer 'n' here, and if you really
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- want to use 'data=ordered' mode, set it in the filesystem itself
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- with 'tune2fs -o journal_data_ordered'.
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-
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- But if you really want to enable the legacy default, you can do
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- so by answering 'y' to this question.
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+ The journal mode options for ext3 have different tradeoffs
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+ between when data is guaranteed to be on disk and
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+ performance. The use of "data=writeback" can cause
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+ unwritten data to appear in files after an system crash or
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+ power failure, which can be a security issue. However,
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+ "data=ordered" mode can also result in major performance
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+ problems, including seconds-long delays before an fsync()
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+ call returns. For details, see:
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+
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+ http://ext4.wiki.kernel.org/index.php/Ext3_data_mode_tradeoffs
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+
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+ If you have been historically happy with ext3's performance,
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+ data=ordered mode will be a safe choice and you should
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+ answer 'y' here. If you understand the reliability and data
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+ privacy issues of data=writeback and are willing to make
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+ that trade off, answer 'n'.
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config EXT3_FS_XATTR
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bool "Ext3 extended attributes"
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