Extending SSD Lifetimes with Disk Based Write Caches
We present Griffin, a hybrid storage device that uses a hard disk drive (HDD) as a write cache for a Solid State Device (SSD) Griffin is motivated by two observations: First, HDDs can match the sequential write bandwidth of mid range SSDs. Second, both server and desktop workloads contain a significant fraction of block overwrites. By maintaining a log structured HDD cache and migrating cached data periodically, Griffin reduces writes to the SSD while retaining its excellent performance. We evaluate Griffin using a variety of I/O traces from Windows systems and show that it extends SSD lifetime by a factor of two and reduces average I/O latency by 56%
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