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#1 2009-12-28 12:47:53
- beroal
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- From: Ukraine
- Registered: 2009-06-07
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ext3, ext4, crash, data loss
As you know, an OS crash may lead to reducing of size of an opened for writing file to zero, i.e. to data loss, see http://en.wikipedia.org/wiki/Ext4#Delay … _data_loss. Is there an example, how am I supposed to work with files to avoid data loss; not a hand-wavy explanation, but an example. I just want a file system to behave like a database, i.e. to perform update of a file in a single transaction. BTW is this problem present in btrfs, nilfs?
we are not condemned to write ugly code
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#2 2009-12-28 13:18:17
- Barrucadu
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- From: York, England
- Registered: 2008-03-30
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Re: ext3, ext4, crash, data loss
The `sync` command performs any cached filesystem operations, but I don't know how to stop them from being cached in the first place.
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#3 2009-12-28 14:39:28
- robmaloy
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- From: Germany
- Registered: 2008-05-14
- Posts: 263
Re: ext3, ext4, crash, data loss
'sync' is also a mount option ('defaults' uses async)
also, always have backups of important files
☃ Snowman ☃
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#4 2009-12-28 18:05:30
- beroal
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- From: Ukraine
- Registered: 2009-06-07
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Re: ext3, ext4, crash, data loss
The `sync` command performs any cached filesystem operations, but I don't know how to stop them from being cached in the first place.
I am afraid that "sync" does not replace transactions. E.g. I open a file and perform a long-term write. During it OS crashes. This reduces file size to zero, is not it?
we are not condemned to write ugly code
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