LVM2's caches

• Given the name of a VG, how do I find which disks it is on?

• • LVM2 caches this information as and when the system sees it.
  • It doesn't generally trust this cache though in case something changed without its knowledge.

• While LVM2 is manipulating a Volume Group, it holds an exclusive lock, so it can cache the metadata.

• We're moving towards sending notifications when things change and caches that can be trusted.