3 ms·
The CPU data caches are low latency and high throughput if you hit them. There is nothing more to it. The interesting questions are: * What is your cache hit r
by crest 7y ago
The CPU data caches are low latency and high throughput if you hit them. There is nothing more to it. The interesting questions are:
* What is your cache hit rate?
* How much of each cache hit is used?
* Are you utilizing all available resources e.g. memory channels, cache banks, vector lanes?
- hinkley 7y agoI took "Random access into the cache" to mean "random access of memory locations that are already in the cache". That would be a cache hit rate of 100%. Which would imply that pointer chasing has seen none of the improvements that branch prediction has seen over that interval (see also, 'threaded interpreters' are now considered passé). Is there a different interpretation I was meant to take from that sentence?
- wpietri 7y agoI'm sure you already know this, but if I understand hinkley's question correctly, there's one more thing to it. Modern processors may prefetch memory in chunks, greatly speeding up the sequential case: https://software.intel.com/en-us/articles/optimizing-application-performance-on-intel-coret-microarchitecture-using-hardware-implemented-prefetchers https://software.intel.com/en-us/articles/optimizing-applica...