Looking at the Phoronix benchmark here: https://www.phoronix.com/scan.php?page=article&item=linux414-bcache- raid&num=2 I think it might be idle hopes to think bcache can be used as a ssd cache for btrfs to significantly improve performance.. True, the benchmark is using ext. But the most important one (where btrfs always shows to be a little slow) would be the SQLLite test. And with ext at least performance _degrades_ except for the Writeback mode, and even there is nowhere near what the SSD is capable of. I think with btrfs it will be even worse and that it is a fundamental problem: caching is complex and the cache can not how how the data on the fs is used. I think the original idea of hot data tracking has a much better chance to significantly improve performance. This of course as the SSD's and HDD's then will be equal citizens and btrfs itself gets to decide on which drive the data is best stored. With this implemented right, it would also finally silence the never ending discussion why not btrfs and why zfs, ext, xfs etc. Which would be a plus by its own right. -- 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
