ATM our retention schema looks like this (https://github.com/wikimedia/operations-puppet/blob/production/manifests/role/graphite.pp#L43)
[default] pattern = .* retentions = 1m:7d,5m:30d,15m:1y,1h:5y
the 1h archive takes ~half the space, it'd be easy to drop that to 3y for example
# whisper-info carbon/agents/graphite1001-a/avgUpdateTime.wsp maxRetention: 157680000 xFilesFactor: 0.5 aggregationMethod: average fileSize: 1170784 Archive 0 retention: 604800 secondsPerPoint: 60 points: 10080 size: 120960 offset: 64 Archive 1 retention: 2592000 secondsPerPoint: 300 points: 8640 size: 103680 offset: 121024 Archive 2 retention: 31536000 secondsPerPoint: 900 points: 35040 size: 420480 offset: 224704 Archive 3 retention: 157680000 secondsPerPoint: 3600 points: 43800 size: 525600 offset: 645184