Re: backing up ext4 fs, system unresponsive, thrashing like crazyeven though swap is unused

From: Eric Paris
Date: Mon Dec 03 2012 - 13:47:05 EST

On Mon, Dec 3, 2012 at 12:43 PM, Theodore Ts'o <tytso@xxxxxxx> wrote:

> If you are seeing a large number of inodes still in the ext4 inode
> cache after using drop_caches, then I'd look to see whether you have
> something like SELinux or auditing enabled which is pinning a bunch of
> dentries or inodes

You can safely ignore this suggestion as it does make sense. SELinux
only grabs a references to dentries during its call to
fs_ops->getxattr, which can't last a meaningful length of time (unless
the filesystem is busted). It only grabs references to inodes during
system initialization, when you couldn't have many in core.

Audit, likewise, only grabs a reference to a dentry during execve()
and only long enough to run getxattr and does not grab any reference
directly to an inode at all.

> or whether your backup program (or some other
> program running on your system) is keeping lots of directories or
> inodes open for some reason.

Certainly could be this suggestion though..
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at