|
|
|
|
|
by JoachimSchipper
3670 days ago
|
|
Idle question: is 50 GB/s a reasonable throughput to expect for such a monster? DDR4 has a peak transfer rate of ~12.8-19.2 GB/s per stick (per https://en.wikipedia.org/wiki/DDR4_SDRAM), so I'd expect quite a bit more bandwidth for predictable accesses - are you using some useful rule-of-thumb, or just unduly pessimistic? ;-) |
|
That is because a memory transaction involves "opening" a page, and then "doing the operation", which can be one to several hundred locations long. "Pointer chasing", code that reads in a structure, then deferences a pointer to another structure, then derefences that pointer to still another stucture, Etc. was really hard on the memory subsystem. It burned a lot of memory ops reading relatively small chunks of memory.
Its a great topic in systems architecture and there are a number of papers on it.