dd command works very slowly

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armuser
Posts: 1
Joined: 1. Dec 2008, 22:29

dd command works very slowly

Post by armuser »

Hi,
I'd like to ask about a performance. I use linux as a guest os and vista home premium as a host. I noticed that dd on linux works very slowly. Simple copying files is fast. I don't know why there are performance problems with dd commands. Is there any any solution?

regards
Jack
TerryE
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Post by TerryE »

Can you quantify this with any performance data?
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fixedwheel
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Joined: 13. Sep 2008, 02:18

Re: dd command works very slowly

Post by fixedwheel »

armuser wrote:I don't know why there are performance problems with dd commands.
quite simple, dd reads and then writes one by one byte, this is the default

specify dd if=<infile> of=<outfile> bs=<bytes>

bs=1M seems to work well inside vbox machines with virtual disks, in real life i use half of the HDD hardware cache size
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