Xyratex -
Checking and repairing large file systems has become one of the
biggest challenges facing the technology. The utility that does this
goes by the name of “fsck”, and it iterates over the entire content of a
file system checking for the integrity of the (relational) data
structures. The problem is that it takes a very long time to run fsck
on current, large file systems.
Why do we need checkers? Early
file systems, like ext2, had no transactional recovery mechanisms and
were checked and repaired after all “un-clean” shutdowns, such as abrupt
power down of systems. That was improved with a next generation of
file systems, which had shadow trees (WAFLE) or journals (ext3) to
recovery. Now almost all recovery of file systems proceeds without
checking and repairing. But it was not the end of fsck. ... 続きを読む
http://blog.xyratex.com/2011/11/28/repairing-and-checking-file-systems/
2011/11/29
Repairing and Checking File Systems:
