What is the effect of AHCI on the performance of solid-state drives?

In the age of mechanical hard drives, few users are concerned about what kind of mode your hard disk is working in, such as the IDE or AHCI. In fact, the IDE and AHCI are two different interface modes, the former being to simulate a SATA disk map into a normal IDE hard disk and not to support new technologies from any SATA interface The latter advanced host Controller interface, which supports a new series of Intel Technologies.

SSD Solid State Hard disk

Why do people now start to mention SATA mode? It's actually because of the advent of solid-state drives. Before the mechanical hard drive performance generally, whether it is open that mode has little effect. However, when the high speed SSD opens AHCI, it supports NCQ (nativecommandqueuing, native command queue), and when the queue depth (QD) increases, performance increases at a geometric level, while the IDE does not support NCQ, and the queue depth increases performance without much change.

To adjust disk mode in the BIOS

Solid state hard disk performance comparison in IDE and AHCI two modes
CDM test the	ide mode	continuous read/write speed	290.5/386.4	485.7/420.6
random 512K read/write speed	288.6/335.2	random 4K read/write speed	23.88/60.14	25.70/65. The
random 4K QD32 read/write speed	2 7.81/77.16	295.3/279.6

By comparing test scores, SSD runs in a different mode than AHCI and the IDE, with significant performance differences. Continuous reading and writing gap between 10%-40%, especially when the queue depth (QD) increase, the gap is particularly obvious. Take 4 K QD32 read as an example, from 295.3mb/s plunged to 27.81mb/s, the decline as much as 90%. In combination, AHCI and IDE mode, the percentage of SSD performance gap is more than 60%, so before installing the new system, be sure to look at your own hard drive mode.