We are working on a small NAS server for home user. The product is equipped with a small fast SSD (around 60-120GB) and a large HDD (2T to 4T). We have two choices: 1. using bcache to accelerate io operation 2. combining SSD and HDD into a single btrfs volume. Bcache is certainly designed for our purpose. But bcache requires complex configuration and can only start from clean disk. Also in our test in Ubuntu 16.04, data inconsistence was observed at least once, resulting total HDD data lost. So we wonder if simply putting SSD and HDD into a single btrfs volume, in whatever mode, the general read operation (mostly readdir and getxattr) will also be significantly faster than a single HDD without SSD. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
