Q What is sequential write speed?

A A measure of how quickly large files can be written to a device.

---

Sequential write is a disk access pattern whereby large contiguous blocks of data are written to adjacent locations on the surface of a device at a queue depth of one. The term is used primarily within the context of benchmarking and the speed is usually measured in MBps. This type of access pattern is common when writing large files such as video, music and high definition images. As a rule of thumb approximately 50% of typical disk access on a PC will consist of sequential reads and writes. Drives that are used primarily for large multimedia files or backups should have relatively high sequential write speeds. When manufacturers quote speeds for devices such as flash drives, hard drives and SSD's, unless otherwise specified, they are referring to the sequential speed. Other types of write speed include random 4k and deep queue depth.