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Date: Tue, 23 Sep 2008 11:04:13 -0400
From: "Joachim Rosenfeld" <joerosenfeld@gmail.com>
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Subject: blocksize when using dd to copy disks? bigger = better?
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When mirroring a disk with dd, I notice that a blocksize of 512 runs
awfully slow, but with bs=1MB (2^10bytes), it runs fairly quickly.

Can someone explain the implications of this? Did all the data not
copy properly with the larger blocksize?

thanks
Joe