Prevent initial-RoI ROB prefetching from running unconditionally with small menu
The ROBPrefetchingAlg
instances used for initial-RoI ROB prefetching use all "L1 Decisions" as input and rely on their ChainFilter
property to execute the prefetching only for the active initial RoIs rather than all of them. When running a test job with a single menu slice or with just a few chains (using selectChains
), it may happen that no chain is defined in the menu that requires one of the three predefined initial-RoI prefetching algs (Si, Calo, Muon). In this case, the ChainFilter
becomes empty which results in unconditional prefetching of ROBs for all initial RoIs even when not needed.
Prevent this issue by forcing ChainFilter
to be a list with a single dummy value which doesn't match any chain. This effectively creates a never-passing ChainFilter
disabling the alg's functionality.
The issue doesn't affect production (P1 data-taking) because we never run with such limited menu online, but it makes local testing difficult.
Jira: ATR-26202