have a small problem in use of dd

Question

I have a small problem in use of dd, actually I read this topic: How to create a bootable Ubuntu USB flash drive from terminal? and I cannot understand some things,Now my question is: whats the meaning of "bs=X" and "&& synce" in dd?

IIRC bs=`block size` when reading and writing from same drive a higher block size will reduce disk thrashing, ie constant head seeking, reading, seeking and writing. In your case `if` and `of` are different drives so it's a mute point I think. Default is `512` but some recommend `32MB`. As for `sync` - related: https://askubuntu.com/questions/706670/why-is-the-sync-option-used-with-the-dd-command — WinEunuuchs2Unix, Jul 08 '17 at 22:49

score 0 · Accepted Answer · edited Jun 12 '20 at 14:37

0

From man dd, with many more options avalable:

bs=BYTES

         read and write up to BYTES bytes at a time

You'd usually use Mega Bytes, for example bs=4M or bs=4096.

&& sync is there to flush buffers after dd is finished.

edited Jun 12 '20 at 14:37

Community

answered Jul 08 '17 at 22:50

mikewhatever

1 Answers1