Robert Milkowski wrote:
Hello Dan,
Tuesday, April 17, 2007, 9:44:45 PM, you wrote:
How can this work? With compressed data, its hard to predict its
final size before compression.
Because you are NOT compressing the file only compressing the blocks as
they get written to disk.
DM> I guess this implies that the compression only can save integral numbers of
DM> blocks.
Can you clarify please?
I don't understand above....
If compression is done block-wise, then if I compress a 512-byte block to 2
bytes, I still need a 512-byte block to store it.
Similarly, if I compress 1000 blocks to 999.001 blocks, I still need 1000
blocks to store them.
This is not a significant problem, I'm sure, but it's worth remembering.
Many tiny files probably don't benefit from compression at all, rather than
"only a little".
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