HI I make bcache device using NVMe ssd device as cache and 4T SATA disk as backing device. I found write performance is extremely poor in writeback cache_mode but raw ssd has very high performance. I monitored io workload using iostat for a while, so I'm sure it really worked in writeback mode. can anyone explain this problem？ Is there any compatible issue with special hardware? -- To unsubscribe from this list: send the line "unsubscribe linux-bcache" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
