Create a 100MB file for testing transfer speed

dd if=/dev/random of=bigfile bs=1024 count=102400

3
By: amiga500
2009-02-17 05:41:20
dd

What Others Think

/dev/random is a blocking device that will block read when the entropy pool is empty. You should use /dev/urandom instead. But even /dev/urandom is cpu intensive, wich is not a good idea if you are testing data transfer speed. A better alternative should be: dd if=/dev/zero of=bigfile bs=1024 count=102400
berta · 560 weeks and 6 days ago
This is only cpu intensive when you generate the file. After that there is no more overhead except for the bandwidth consumed. I have a small shell script that compares the downloaded checksum with one done on the generated file, then prints the results (either checksums match or they don't).
meganerd · 407 weeks and 6 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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