:1) The Update a Clone Method

:

:2) The Update in Place Method

:

:Daniel
    Hmm.  Those seem fairly complex.  How would you deal with incidental

    operations on the B-Tree such as doing a split?  A single insert

    could wind up requiring a split of every internal node on the way

    down to the leaf.  I guess you could clone the blocks, but there are

    a ton of parent and child linkages that have to be changed when you

    split a node.  It sounds pretty expensive.
    Maybe implementing UNDOs for incidental B-Tree operations is the ticket.

    Incidental meaning those operations (such as splits) which lead up to

    an insertion or deletion but do not actually perform the insertion

    or deletion.   On crash recovery you would undo partially completed

    B-Tree operations and then REDO the related logical operations.
    Having to allocate new blocks for B-Tree deletions could create a big

    issue when the filesystem becomes full or near-full.
					-Matt

					Matthew Dillon 
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