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by theevilsharpie 2172 days ago
AMD is doing well in the CPU market today _because_ they reversed course from the Bulldozer-based architectures.
1 comments

More than that, Bulldozer didn't even have good single thread integer performance. What it gave you was 8 cores that might be able to keep up with 4 of Intel's cores on something that has 8 threads. The market was not particularly interested in this, especially since at the time even fewer things could actually use 8 threads than they do now.
Bulldozer significantly outperformed Sandy Bridge on the workloads which it was designed to be good at, which is multi-threaded integer workloads, like compiling the Linux kernel.

https://www.phoronix.com/scan.php?page=article&item=amd_fx81...

https://www.phoronix.com/scan.php?page=article&item=amd_fx83...

If Linus' attitude of "I'd rather have more cores" and "FP doesn't really matter" were representative of market demand, you'd have expected Bulldozer to do well at least somewhere, as opposed to nowhere.

Are we looking at the same benchmarks? In the first they're comparing an 8-core Bulldozer to Sandy Bridge with 4 cores and no hyperthreading and it's basically even, sometimes it wins by a small margin on the threaded ones. In the second the 3770K has 4 cores with hyperthreading and that makes it look even worse.

If they were actually getting twice the integer performance per module as Intel was getting per core then it might've been interesting, but being the same or only slightly better when comparing modules to cores wasn't enough to overcome the single thread performance deficit which people still care about a lot.

You have to look for them, but there are benchmarks where AMD outperforms significantly. I cant find the Linux compilation benchmark now, but the difference was not small.

The Bulldozer really did have a big advantage in integer throughput per dollar, but that does not translate to a 2x speedup in pretty much any benchmark. FP throughput on the other hand shows up a lot.

I think we'd have been rather better off buying a load of Magny Cours rather than Sandybridge for a university HPC system whose procurement I wasn't sufficiently involved in.