B is owner of k,v1
A has k,v1 in L1
1. TX: A puts k,v2
2. TX: A sends async PrepareCommand k,v2 to B (one-phase-commit)
3. TX: A removes k,v1 from L1
4. A putForExternalRead k,v1 and has it in L1 again
5. TX: B executes PrepareCommand k,v2 but doesn't send invalidation to origin

Result: A has k,v1 and B has k,v2

Solution: For async caches send invalidation to origin too.

The problem is that the owner updates the cache entry asynchronously. This gives the origin of the transaction time to request the entry. Here an outdated version is received and placed in L1. The owner never invalidates the entry and as result the cache is inconsistent.