DDR3 -> SGDMA -> TSE throughput

[Altera_Forum]

I've got a Qsys system where I'm buffering up data into a DDR3 and then DMAing it to the TX port on my Triple Speed Ethernet. The DDR3 is running at 333Mhz. The rest of the Avalon components including the TSE are using a 100Mhz clock.  

 I'm only able to achieve about 160Mb/s with this configuration.   With the same Qsys system I can do OnChipMem -> M2M_DMA -> TSE and achieve 980Mb/s.  How can I speed up the DDR3 -> SGDMA -> TSE path?  Would making the rest of the Avalon parts run at 83.3333Mhz be better than 100 since it is a multiple of the DDR3 frequency?   Thanks!