Ufs vs emmc memories: what are they and how do they influence mobile performance

For some time now, different phone manufacturers are emphasizing the types of UFS memory. Models like the Xiaomi Mi A3 or the OnePlus 7 and 7 Pro have UFS 2.1 and UFS 3.0 memories respectively, but these are not the only ones. Currently we can find eMMC type memories whose main market is closely linked to mid-range and low-end phones. What are the differences between UFS vs eMMC memories really? Do they influence the final performance of the mobile and its durability over the years? We see it.

eMMC and UFS: what are they and what speed differences are there

Like hard drives in laptops and desktops, there are different types of memory, the main difference being the maximum reading and writing speed. If the latter are the most common types of memory are hard drives and solid state memories (SSD), in mobile phones the most common is to find eMMC and UFS memories.

EMMC memories, the "hard drives" of mobile phones

The eMMC (embedded MultiMediaCard) type memories are a type of NAND flash memory, that is to say, memories soldered to the board, whose particularity lies in the use of a system very similar to that of current SD and micro SD cards.

The Huawei P20 Lite has a type of memory eMMC 5.1.

Said system is based on the integration of the memory controller in the unit module itself, in such a way that components such as the processor are exempt from performing operations related to the use of memory. This directly affects the read and write operations demanded by the CPU. By having a single parallel interface, better known as a unidirectional interface, we can only perform operations in a single direction, that is, we can only write or read data, never at the same time or simultaneously.

The target or main audience for this type of memory is based, as we mentioned at the beginning of the article, on mid-range and low-range mobiles and tablets, as they have a cheaper and less complex manufacturing process than UFS memories. The latest eMMC memory standard, by the way, is the eMMC 5.1 standard.

UFS memories, the SSD of the portable era

UFS (Universal Flash Storage) memories are defined as a type of NAND memory based on the SCSI architecture whose main characteristic is based on the possibility of sending several writing and writing requests at the same time, by having a bidirectional interface.

Another defining characteristic of this type of memory is the QC command queue. This queue stores and orders the commands received by the processor, which are executed simultaneously according to the priority of the user when launching applications or executing read and write operations. It should also be noted that its implementation has a more advanced SATA interface than those of eMMC memories.

Models like OnePlus 7, Xiaomi Mi 9, Samsung Galaxy S10 or Huawei P30 Pro are some of the best known phones that implement this type of memory, although in different versions (UFS 2.1, UFS 3.0…). The latest standard released by Samsung, the design company, is UFS 3.0.

UFS 3.0 vs eMMC 5.1, these are their speed differences

Beyond the technical data, where the main difference between UFS vs eMMC memories lies is in the speed of sequential and random read and write. To test a table comparing the theoretical speeds that this type of memory offers us:

	eMMC 5.1	UFS 2.1	UFS 3.0 (theoretical data for 512GB modules) *
Sequential read speed	282 MB / s	749 MB / s	2,100 MB / s
Sequential write speed	92 MB / s	142 MB / s	410 MB / s
Random read speed	29 MB / s (7,438 IOPS)	156 MB / s (40,722 IOPS)	63,000 IOPS
Random write speed	14 MB / s (3,694 IOPS)	149 MB / s (38,247 IOPS)	68,000 IOPS

As we can see in the comparison table, where there is the main difference in speed is in the random writing and reading operations, that is, in operations such as opening applications or saving data in the cache.

This directly influences the performance of the device, in such a way that we can obtain up to double and even triple the speed in the operations mentioned above on phones with eMMC memory compared to mobile phones with UFS memory.