Changing filesystem resize patterns

Changing filesystem resize patterns

In addition, many cloud providers charge their customers based on the size of the virtual block device being used, which means that customers have good reason to wait until the filesystem is nearly full before expanding it. A common pattern is that once a filesystem gets, say, 99% full, another 1GB or 5GB are added; that pattern repeats over and over for the filesystem. "That tends to result in worst-case filesystem fragmentation." Most filesystems are not designed to work well when running nearly full, he said.

In the case of XFS, for instance, is it better to use lvmthin(7) to thinly provision storage, adding more PVs to the VG containing a thin pool LV before it runs out of space; or is it better to resize and then run xfs_fsr to defrag?

I suppose that: if you've been 99% full for a while, and have lots of fragmentation, and the only expand by a small amount; is it possible there's not enough free space to allow ideal defragmentation? Or does the defragmentation operation potentially just take a long time?