2
votes
4answers
104 views

Why is dd so slow on raw device, so fast on filesystem (writing on USB key)?

I have a USB key that I am trying to benchmark quick'n'dirty on Linux. dd on raw partition I'm testing write bandwith. I created a partition starting at sector 2048, then did a 4 GB sequential ...
4
votes
2answers
2k views

Benchmark ssd on linux: How to measure the same things as crystaldiskmark does in windows

I want to benchmark a ssd (possibly with encrypted filesystems) and compare it to benchmarks done by crystaldiskmark on windows. So how can I measure approximately the same things as ...
4
votes
1answer
2k views

What's faster, dd 1.5TB or rsync 500GB?

I need to save data from a failing hard drive. Sounds like ddrescue or myrescue (or maybe clonezilla?) will be my best friends here, but I'm just wondering what will likely be faster: using ...
24
votes
4answers
7k views

Is there a way to determine the optimal value for the bs parameter to dd?

On occasion I've seen comments online along the lines of "make sure you set 'bs=' because the default value will take too long," and my own extremely-unscientific experiences of, "well that seemed to ...