What is Write Amplification?

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What is Write Amplification?
Write amplification is an internal issue for NAND flash SSDs that arises from the way that NAND chips work. It doesn’t exist in standard HDDs, nor did it exist in DRAM SSDs before we had NAND ones. In a nutshell it’s the number of times that a NAND chip within an SSD is written to after the host computer performs a single write.