Universal Flash Storage or UFS is a flash storage specification and a specific high-performance solid-state storage interface developed for digital cameras, smartphones and tablet computers, and other consumer electronic devices.
The creation of the Universal Flash Storage Association in 2010 started the promotion of UFS as a replacement to other flash storage standards such as the MultiMediaCard and Embedded MultiMedia Card. It was in 2014 when it started to replace eMMC as an internal storage solution for portable consumer electronic devices such as smartphones.
Samsung unveiled an embedded Universal Flash Storage based on UFS 3.0 during the 2018 Mobile World Congress. Version 3.1 was introduced in 2020 by JEDEC Solid State Technology Association as a faster, more energy-efficient, and inexpensive internal storage solution.
Pros of UFS: Advantages of Universal Flash Storage
Introduces a Universal Flash Storage Standard
Standardization is one of the primary reasons for developing the Universal Flash Storage Technology. The developers positioned it as a replacement for Secure Digital or SD cards, Embedded MultiMediaCard, and other prior embedded internal storage solutions. Part of their intention was to reduce market confusion and remove the need for using different adapters for different types of removable and attachable memory cards.
Relatively Better Read and Write Performance
One of the notable advantages of UFS is its performance. Note that eMMC is faster than SD cards. However, when compared against Universal Flash Storage, it lags in data transfer speeds. An eUFS 3.0 has a sequential read speed of 2100 MB/s and sequential write speed of 410 MB/s, while eMMC 5.1 has 250 MB/s sequential read speed and 125 MB/s sequential write speed. The selling point of UFS is to deliver SSD-like speed on mobile devices.
Superior Architecture through a Serial Interface
Note that MMC and eMMC are inherently slower than Universal Flash Storage and solid-state drives based on PCIe and NVMe because they have a parallel interface. This means that it uses a single lane each way during data transfers, and it cannot read and write data at once. UFS has a serial interface that means it can both read and write data at the same time.
Ideal for Portable Devices Due to Energy Efficiency
Power efficiency is another strength of Universal Flash Storage. When compared to an eMMC, an eUFS is twice as energy efficient when idle. The introduction of Version 3.0 provides the same conservative power consumption feature despite significant improvements in data transfer speeds. The technology works as if it is an ultra-compact solid-state drive. These characteristics make it ideal for small consumer electronic devices.
Cons of UFS: Disadvantages of Universal Flash Storage
Short Lifespan Due to Write-Erase Cycles Limitation
One of the major drawbacks of flash storage and solid-state drives is their short lifespan due to limitations in write-erase cycles. Hard disk drives do not have this problem. This is also one of the biggest disadvantages of UFS. There is a limit to the number of write-erase cycles a flash block can accept. Each cycle results in the deterioration of the oxide layer of a memory cell. Nearing and reaching the limit would produce errors until the storage integrity starts to fail.
Advantage of NVMe-Based Solid State Storage Over UFS
Universal Flash Storage is the dominant internal storage solution for smartphones and tablets. Mid-level to flagship Android devices use this protocol. But the introduction of the iPhone 6S in 2015 has challenged its performance advantages. Apple modified the NVMe protocol and develop a custom PCIe controller to use an SSD-based storage in iPhones. Note that this same protocol is the reason why MacBook devices are inherently faster than laptops that use other SSD interfacing protocols.