IT House news on February 24, when testing the impact of power outages on cached data, Apple programmer Russ Bishop noticed that some NVMe SSDs would lose data even after the cache was completely refreshed.
SSD power-down protection (PLP) refers to protecting an SSD during and after a power-out event, safely flushing data in process (or data residing in a DRAM or SRAM cache buffer) into persistent or non-volatile flash memory, and maintaining the integrity of the SSD mapping table so that the SSD can be recognized and available again after a system restart.
However, Bishop's tests showed that the feature was missing in some NVMe SSDs or did not work as expected.
IT House learned that Bishop tested several SSDs, some of which worked properly to prevent data loss, as follows:
Samsung 970 EVO Plus
WD Red SN700
Crucial P5 Plus 1TB
Kingston SNVS/250G
Seagate Firecuda 530 PCIe Gen 4 1TB
Intel 670p 1TB
Crucial P2 250GB
Samsung 980 250GB
WD Black SN750 1TB
WD Green SN350 240GB
The SSD models for the lost data are:
SK Hynix Gold P31 2TB
Sabrent Rocket 512
In addition, some SSDs, such as the Intel 670, degrade performance when reconnected after a power outage, but recover after a period of time.