Raikv Alternatives

raikv reviews and mentions

• New x86 micro-op vulnerability breaks all known Spectre defenses
  1 project | news.ycombinator.com | 1 May 2021

  I have a graph for this:

  https://github.com/raitechnology/raikv/blob/master/graph/mt_...

  The CPU in this case is a Threadripper 3970x, 32 cores, 64 SMT.

  My experience is this: When the L3 cache is effective, then the memory latency hiding via memory prefetch works well across SMT threads. If the hashtable load requires a chain walk, the SMT latency hiding is less effective because the calculated prefetch location is not the actual hit. I couldn't get prefetching multiple slots as the load increased to be as effective as prefetching a single slot.

• Performance comparison: counting words in Python, Go, C++, C, Awk, Forth, Rust
  16 projects | news.ycombinator.com | 15 Mar 2021

  Amusingly, I've done a multi-threaded version of the word counting program in order to test a shm kv store. I needed benchmark that created a lot of cross thread concurrent accesses to keys and I found a blog about this test. My version has serious constraints though, you have to create a shared memory map with enough space to hold all of the keys beforehand, as it doesn't resize the shm kv map as it runs.

  This is the source for it:

  https://github.com/raitechnology/raikv/blob/master/test/ctes...

  The speedup of the multi-threaded version vs the single-threaded version is about linear. The single threaded version uses 2 threads, one to read stdin and one to hash the keys, the 16 threaded version uses one thread to read, 16 to hash.

  $ time ctest -t 1 < ~/data/enwiki-p10p30303