If M1 and M2 both operate over the same partition key they won’t be separate mutations, they should be combined into a single mutation before submission to SP.mutate
> On 19 Aug 2022, at 10:05, Claude Warren, Jr via dev > <dev@cassandra.apache.org> wrote: > > > > # Table definitions > > Table [ Primary key ] other data > base [ A B C ] D E > MV [ D C ] A B E > > > # Initial data > base -> MV > [ a b c ] d e -> [d c] a b e > [ a' b c ] d e -> [d c] a' b e > > > ## Mutations -> expected outcome > > M1: base [ a b c ] d e' -> MV [ d c ] a b e' > M2: base [ a b c ] d' e -> MV [ d' c ] a b e > > ## processing bug > Assume lock can not be obtained during processing of M1. > > The mutation M1 sleeps to wait for lock. (Trunk Keyspace.java : 601 ) > > Assume M2 obtains the lock and executes. > > MV is now > [ d' c ] a b e > > M1 then obtains the lock and executes > > MV is now > [ d c ] a b e' > [ d' c] a b e > > base is > [ a b c ] d e' > > MV entry "[ d' c ] a b e" is orphaned > >
