In short, eDRAM is a larger memory available on the CPU chip itself. Does it acts like a 4th level of cache? It is nearer to the processors than main memory and is much faster.
In Intel Skylake, the integrated Iris Pro GPU can also utilize this.
cuiwei
eDRAM does not act solely as a level 4 cache, because, note in the diagram, that other devices can access eDRAM without going through LLC. A more accurate term I would use is that eDRAM serves as a faster buffer to DDR. And since every memory requests, eDRAM or DDR, goes through eDRAM CTL, the architecture allows the eDRAM to stay coherent with DDR and therefore transparent to applications(thus programmers)
In short, eDRAM is a larger memory available on the CPU chip itself. Does it acts like a 4th level of cache? It is nearer to the processors than main memory and is much faster.
In Intel Skylake, the integrated Iris Pro GPU can also utilize this.
eDRAM does not act solely as a level 4 cache, because, note in the diagram, that other devices can access eDRAM without going through LLC. A more accurate term I would use is that eDRAM serves as a faster buffer to DDR. And since every memory requests, eDRAM or DDR, goes through eDRAM CTL, the architecture allows the eDRAM to stay coherent with DDR and therefore transparent to applications(thus programmers)