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After flattening service serialized WORM objects and wrote them to DT-blob, these objects can be evicted from DRAM. DAOS stores the BIO address of evicted object in the object index tree, which always stay in DRAM. When read request against evicted object arrived at server, if VOS found the object has already been evicted from DRAM, it can read the entire object back by one BIO call.

Read handling of flattened WORM object

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