> I wonder that most consumer SSDs are aimed to power loss safe (by implementing like CoW?) even without capacitor but I don't know the truth. The flash transl

> I wonder that most consumer SSDs are aimed to power loss safe (by implementing like CoW?) even without capacitor but I don't know the truth. The flash translation layer in a SSD looks a lot like a journalling or log-structured filesystem, and without power loss protection capacitors you get similar data integrity guarantees: unexpected power loss may mean loss of recently written data (still in the drive's write buffers, and maybe stuff in partially-written NAND pages), but shouldn't cause catastrophic loss of data. You generally have more data at risk from being buffered in main system RAM by the OS than you do from the volatile/unprotected buffers in the SSD itself. The SSD should never be erasing a block as part of a garbage collection process until the live data from that block has been committed to a new block.