Data security in a multi-nodal environment

An apparatus comprising:

• a computer system comprising a plurality of compute nodes, each with a processor and a memory coupled to the processor;
• a plurality of running execution units in the memory of the compute nodes and executed by the processors of the compute nodes;
• a relationship record for each of the plurality of running execution units, where each relationship record includes a time relationship, a data relationship and a service relationship, wherein the time relationship indicates whether a first execution unit can execute within a given time period with at least one of the plurality of running execution units;
• and
• a security manager that enforces security of data on the computer system by managing the execution of the first execution unit and the plurality of running execution units depending on the relationship records;
• wherein the time period is zero such that the time relationship indicates that the execution unit cannot run concurrently with the another execution unit;
• wherein the data relationship indicates whether the first execution unit can execute depending on data currently in use in at least one of the plurality of running execution units;
• and
• wherein services relationship indicates whether the execution unit can execute depending on a service request in at least one of the plurality of running execution units.