https://bugzilla.kernel.org/show_bug.cgi?id=151491 Bug ID: 151491 Summary: free space lossage on busy system with bigalloc enabled and 128KB cluster Product: File System Version: 2.5 Kernel Version: 4.1.8 Hardware: x86-64 OS: Linux Tree: Mainline Status: NEW Severity: high Priority: P1 Component: ext4 Assignee: fs_ext4@xxxxxxxxxxxxxxxxxxxx Reporter: mlmartin@xxxxxxxxxxxxxxxxx Regression: No Created attachment 227581 --> https://bugzilla.kernel.org/attachment.cgi?id=227581&action=edit details of fault with scripts for reproduction file system with bigalloc enabled and 128KB cluster size with a large number of 2MB files being created/overwritten/deleted loses usable space. Running du and df gives wildly different usage with df showing much more usage than du. lsof shows no phantom open files. Using dd to fill the file system shows that df's version of free space is operative, but unmounting and remounting the file system returns the free space. There is no difference between df and du usage after remount. The fault does not seem to be present in the 4.7 kernel (or it takes a lot more activity for it to show up). I will build 4.4.16 and retest to see if is present there. We do have a(n obnoxious) workaround of periodically unmounting/remounting files systems. Details of configurations and tests in the attached document -- You are receiving this mail because: You are watching the assignee of the bug. -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
