Automatic and customisable checkpointing

A computer system, comprising:

• a plurality of computation nodes to process data objects by applying to each data object a lineage computation chain, wherein the lineage computation chain comprises a chain of operations recorded in a log;
• a plurality of staging nodes, each staging node assigned to one or more of the computation nodes;
• and
• a network to exchange data including data objects between the computation nodes and the staging nodes and access a file store;
• wherein a staging node:
• duplicates, in a staging memory of the staging node, a data object from a computation memory of a computation node to which the staging node is assigned;
• copies the data object from the computation memory of the computation node to the file store;
• and
• retains the data object in the staging memory of the staging node after copying the data object to the file store;
• wherein to duplicate the data object, the staging node applies said lineage computation chain to the data object retained in the staging memory of the staging node to replicate operations applied to the data object in the computation node without reading the data object from the computation memory of the computation node to the staging node.