Yeah, SSDs are really fast. Have been for a while now, so fast that system call and other kernel overheads easily dominate unless you take care: https://blog.

Yeah, SSDs are really fast. Have been for a while now, so fast that system call and other kernel overheads easily dominate unless you take care: https://blog.metaobject.com/2017/02/mkfile8-is-severely-syscall-limited-on.html https://blog.metaobject.com/2017/02/mkfile8-is-severely-sysc... That was 8 years ago, and even then mkfile needed a 512K buffer size to saturate the hardware. With the 512 byte default buffer it was 8x slower than the hardware. In addition, as others have pointed out, if you are not doing something extra to ensure things are flushed to disk, you are just measuring the buffer cache in the first place.