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- whitespace change only (translators may igore)

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Jason Helfman 2016-03-06 20:19:49 +00:00
parent 18994155f6
commit a50bf6247e
Notes: svn2git 2020-12-08 03:00:23 +00:00 
svn path=/head/; revision=48349
1 changed files with 13 additions and 15 deletions
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en_US.ISO8859-1/books/arch-handbook/driverbasics/chapter.xml
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@ -387,22 +387,20 @@ Closing device "echo".</screen>
operations, depriving the application of the ability to know the operations, depriving the application of the ability to know the
exact disk contents at any one instant in time.</para> exact disk contents at any one instant in time.</para>
<para> <para>This makes predictable and reliable crash recovery of
This makes predictable and reliable crash recovery of on-disk on-disk data structures (filesystems, databases etc.)
data structures (filesystems, databases etc.) impossible. Since impossible. Since writes may be delayed, there is no way
writes may be delayed, there is no way the kernel can report to the kernel can report to the application which particular
the application which particular write operation encountered a write operation encountered a write error, this further
write error, this further compounds the consistency compounds the consistency problem.</para>
problem.</para>
<para> <para>For this reason, no serious applications rely on block
For this reason, no serious applications rely on block devices, devices, and in fact, almost all applications which access
and in fact, almost all applications which access disks directly disks directly take great pains to specify that character
take great pains to specify that character (or (or <quote>raw</quote>) devices should always be used. Because
<quote>raw</quote>) devices should always be used. Because the the implementation of the aliasing of each disk (partition) to
implementation of the aliasing of each disk (partition) to two two devices with different semantics significantly complicated
devices with different semantics significantly complicated the the relevant kernel code &os; dropped support for cached disk
relevant kernel code &os; dropped support for cached disk
devices as part of the modernization of the disk I/O devices as part of the modernization of the disk I/O
infrastructure.</para> infrastructure.</para>
</sect1> </sect1>