Post by George Crump (thank you)
When non-volatile flash memory-based solid-state drives (SSDs) were introduced, the protocol support included SAS/SATA. These interfaces were designed for hard disk drives (HDDs) and had more latency than was ideal for flash, but it made for easier integration of SSDs into enterprise storage systems and servers since the existing infrastructure was built around HDDs. SSDs were forced into the mold of HDD storage including the physical interface, host control interface and storage logic. Though PCIe flash drives became a step in the right direction, they lacked the ease of implementation that SAS/SATA SSDs have and do not fully expose the performance that NAND flash can offer.
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