  In existing systems, to perform any bulk data movement operation (copy or
initialization), the data has to first be read into the on-chip processor, all
the way into the L1 cache, and the result of the operation must be written back
to main memory. This is despite the fact that these operations do not involve
any actual computation. RowClone exploits the organization and operation of
commodity DRAM to perform these operations completely inside DRAM using two
mechanisms. The first mechanism, Fast Parallel Mode, copies data between two
rows inside the same DRAM subarray by issuing back-to-back activate commands to
the source and the destination row. The second mechanism, Pipelined Serial
Mode, transfers cache lines between two banks using the shared internal bus.
RowClone significantly reduces the raw latency and energy consumption of bulk
data copy and initialization. This reduction directly translates to improvement
in performance and energy efficiency of systems running copy or
initialization-intensive workloads
