Hi all, We're running a couple of experiments on our servers with btrfs (kernel version 4.4). And we're running some abrupt power-off tests for a couple of scenarios:
1. We have a filesystem on top of two different btrfs filesystems (distributed across N disks). i.e. Our filesystem lays out data and metadata on top of these two filesystems. With the test workload, it is going to generate a good amount of 16MB files on top of the system. On abrupt power-off and following reboot, what is the recommended steps to be run. We're attempting btrfs mount, which seems to fail sometimes. If it fails, we run a fsck and then mount the btrfs. The issue that we're facing is that a few files have been zero-sized. As a result, there is either a data-loss, or inconsistency in the stacked filesystem's metadata. We're mounting the btrfs with commit period of 5s. However, I do expect btrfs to journal the I/Os that are still dirty. Why then are we seeing the above behaviour. 2. Another test that we're running is to create a virtual disk each on multiple NFS mounts (softmount with timeout of 1 min), and use these virtual disks as individual devices for one single btrfs. What is the expected btrfs behaviour when one of the virtual disk becomes unresponsive for a period of time (say 5 min)? Does the expectation change if the NFS mounts are mounted with sync option? Thanks in advance for any help you can offer. -- -Shyam -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
