## Issue Addressed Closes https://github.com/sigp/lighthouse/issues/2112 Closes https://github.com/sigp/lighthouse/issues/1861 ## Proposed Changes Collect attestations by validator index in the slasher, and use the magic of reference counting to automatically discard redundant attestations. This results in us storing only 1-2% of the attestations observed when subscribed to all subnets, which carries over to a 50-100x reduction in data stored 🎉 ## Additional Info There's some nuance to the configuration of the `slot-offset`. It has a profound effect on the effictiveness of de-duplication, see the docs added to the book for an explanation: https://github.com/michaelsproul/lighthouse/blob/5442e695e5256046b91d4b4f45b7d244b0d8ad12/book/src/slasher.md#slot-offset