4 ms·

I'm guessing it was built and tested internally at Google and no one tested it with bazel. It also depends on smasher, which I believe should be declared in th

by amock 11y ago

I'm guessing it was built and tested internally at Google and no one tested it with bazel. It also depends on smasher, which I believe should be declared in the WORKSPACE file. So unless you want to manually build it you'll have to wait for someone to fix the build.

nkurz 11y ago
I went ahead and created a Makefile: CXXFLAGS := -g -std=c++11 -Wall -O3 -march=native -Wno-sign-compare OBJS := highway_tree_hash.o \ scalar_highway_tree_hash.o \ scalar_sip_tree_hash.o \ sip_hash.o \ sip_tree_hash.o MAIN := sip_hash_main all: $(OBJS) $(CXX) $(CXXFLAGS) $(OBJS) $(MAIN).cc -o $(MAIN) clean: rm -f $(OBJS) $(MAIN) Then I commented out two lines in "sip_hash_main.cc": // #include "smhasher.h" // RunAllTests(argc, argv); Then "make" and run: nate@skylake:~/git/highwayhash$ ./sip_hash_main ScalarSipTreeHash ... GBps=2.44 c/b=1.44 ScalarHighwayTreeHash ... GBps=1.16 c/b=3.02 SipHash ... GBps=1.54 c/b=2.27 SipTreeHash ... GBps=4.56 c/b=0.77 HighwayTreeHash ... GBps=11.49 c/b=0.30 ... The inner loop for HighwayTreeHash looks like this: 0.89 │ 60:┌─→vpor %ymm5,%ymm0,%ymm0 4.47 │ │ vpaddq (%rcx),%ymm1,%ymm1 6.04 │ │ add $0x4,%rax 0.22 │ │ add $0x20,%rcx 2.24 │ │ cmp %rax,%rdi 3.13 │ │ vpsrlq $0x20,%ymm1,%ymm2 3.36 │ │ vpmulu %ymm1,%ymm0,%ymm4 13.20 │ │ vpshuf %ymm3,%ymm4,%ymm4 11.19 │ │ vpmulu %ymm2,%ymm0,%ymm2 │ │ vpaddq %ymm1,%ymm2,%ymm1 31.32 │ │ vpaddq %ymm4,%ymm0,%ymm0 7.61 │ └──ja 60
- forgotpwtomain 11y ago
  Do you know if there is a reference for a comparative number of collisions anywhere e.g. (http://programmers.stackexchange.com/questions/49550/which-hashing-algorithm-is-best-for-uniqueness-and-speed http://programmers.stackexchange.com/questions/49550/which-h...) ?
  - janwas 11y ago
    With a 64-bit hash, you shouldn't be seeing collisions at all on small datasets. A test such as smhasher can verify this.
janwas 11y ago
Thanks for mentioning, I have removed the smhasher dependency. We have an enhanced version of it which cannot be yet be released due to a dependency on threading libraries.

by amock 11y ago

nkurz 11y ago

I went ahead and created a Makefile: CXXFLAGS := -g -std=c++11 -Wall -O3 -march=native -Wno-sign-compare OBJS := highway_tree_hash.o \ scalar_highway_tree_hash.o \ scalar_sip_tree_hash.o \ sip_hash.o \ sip_tree_hash.o MAIN := sip_hash_main all: $(OBJS) $(CXX) $(CXXFLAGS) $(OBJS) $(MAIN).cc -o $(MAIN) clean: rm -f $(OBJS) $(MAIN) Then I commented out two lines in "sip_hash_main.cc": // #include "smhasher.h" // RunAllTests(argc, argv); Then "make" and run: nate@skylake:~/git/highwayhash$ ./sip_hash_main ScalarSipTreeHash ... GBps=2.44 c/b=1.44 ScalarHighwayTreeHash ... GBps=1.16 c/b=3.02 SipHash ... GBps=1.54 c/b=2.27 SipTreeHash ... GBps=4.56 c/b=0.77 HighwayTreeHash ... GBps=11.49 c/b=0.30 ... The inner loop for HighwayTreeHash looks like this: 0.89 │ 60:┌─→vpor %ymm5,%ymm0,%ymm0 4.47 │ │ vpaddq (%rcx),%ymm1,%ymm1 6.04 │ │ add $0x4,%rax 0.22 │ │ add $0x20,%rcx 2.24 │ │ cmp %rax,%rdi 3.13 │ │ vpsrlq $0x20,%ymm1,%ymm2 3.36 │ │ vpmulu %ymm1,%ymm0,%ymm4 13.20 │ │ vpshuf %ymm3,%ymm4,%ymm4 11.19 │ │ vpmulu %ymm2,%ymm0,%ymm2 │ │ vpaddq %ymm1,%ymm2,%ymm1 31.32 │ │ vpaddq %ymm4,%ymm0,%ymm0 7.61 │ └──ja 60

forgotpwtomain 11y ago
Do you know if there is a reference for a comparative number of collisions anywhere e.g. (http://programmers.stackexchange.com/questions/49550/which-hashing-algorithm-is-best-for-uniqueness-and-speed http://programmers.stackexchange.com/questions/49550/which-h...) ?
- janwas 11y ago
  With a 64-bit hash, you shouldn't be seeing collisions at all on small datasets. A test such as smhasher can verify this.

janwas 11y ago

Thanks for mentioning, I have removed the smhasher dependency. We have an enhanced version of it which cannot be yet be released due to a dependency on threading libraries.