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No conservative 2PL doen’t ensure recoverability always.

 

Conservative 2PL – It requires a transaction to lock all the items it accesses before the transaction begins execution.The locks can be released at any point of time, need not after the commit operation.

Just consider this eg:

T1                T2

L_X(A)         

W(A)

U(A)

                 L_X(A)

                 R(A)

                 U(A)

                commit

commit

→ This is clearly an irrecoverable schedule.
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Conservative 2PL ensures recoverability but has cascading rollback, hence they are not cascadeless.

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