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Title

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1		-Linux General Documentation
	1	+Commands

Parent

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1		-iXPath Documentation.WebHome
	1	+Documentation.Miscellaneous.Linux.WebHome

Content

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17	17	down
18	18	{{/code}}
19	19
20		-
	20	+== Test disk speed ==
	21	+
	22	+dd command allows to copy all or parts of a disk by bytes block without impact from content structure of the disk.
	23	+
	24	+(% class="box warningmessage" %)
	25	+(((
	26	+Use dd command with caution as it can cause severe dammage to the system
	27	+Do not use dd to duplicate a disk. Prefer ddrescue command
	28	+)))
	29	+
	30	+Command structure
	31	+
	32	+(% class="box" %)
	33	+(((
	34	+dd if=<source> of=<target> bs=<block size> count=<number of blocks> oflag=<flag>
	35	+)))
	36	+
	37	+oflag: 'dsync' to use synchronized I/O for data
	38	+
	39	+{{code language="shell"}}
	40	+dd if=/dev/zero of=/tmp/test2.img bs=512 count=1000 oflag=dsync
	41	+1000+0 records in
	42	+1000+0 records out
	43	+512000 bytes (512 kB, 500 KiB) copied, 1.22846 s, 417 kB/s
	44	+{{/code}}