dd

dd cheatshet

Create Files

To create a 1GB file:

$ dd if=/dev/zero of=1g.bin bs=1G count=1

Benchmarking

Server Throughput (Streaming I/O):

$ dd if=/dev/zero of=/root/testfile bs=1G count=1 oflag=dsync

Server Latency:

$ dd if=/dev/zero of=/root/testfile bs=512 count=1000 oflag=dsync

Testing Write Speed:

# Set the block size to 1MB and copy 1000 blocks
dd if=/dev/urandom of=testfile bs=1M count=1000

Testing Read Speed:

dd if=testfile of=/dev/null bs=1M