Handling data segments in deduplication

In some embodiments, a method of maintaining a reference list for data deduplication is provided. The method includes discarding a newly arriving data segment in response to finding a fingerprint of the newly arriving data segment matches an existing fingerprint in a plurality of fingerprints on a fingerprint-to-file reference list. The method includes adding, in the fingerprint-to-file reference list, to a list for the existing fingerprint, a source for the newly arriving data segment, in response to the fingerprint-to-file reference list indicating the existing fingerprint does not correspond to a hot data segment and setting an indication in the fingerprint-to-file reference list that the existing fingerprint corresponds to the hot data segment in response to the list for the existing fingerprint meeting or exceeding a predetermined number of entries. Other embodiments are included.