[EMAIL PROTECTED] wrote:
Hello Casper,
Tuesday, December 12, 2006, 10:54:27 AM, you wrote:
So 'a' UB can become corrupt, but it is unlikely that 'all' UBs will
become corrupt through something that doesn't also make all the data
also corrupt or inaccessible.
CDSC> So how does this work for data which is freed and overwritten; does
CDSC> the system make sure that none of the data referenced by any of the
CDSC> old ueberblocks is ever overwritten?
Why it should? If blocks are not used due to current UB I guess you
can safely assume they are free.
What if a newer UB is corrupted and you fall back to an older one?
Casper
A block freed in transaction group N cannot be reused until transaction
group N+3; so there is no possibility of referencing an overwritten
block unless you have to back off more than two uberblocks. At this
point, blocks that have been overwritten will show up as corrupted (bad
checksums).
-Mark
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