Re: lzo2 shows insane speed gap

Christian Weisgerber wrote:
My best guess at this time is that lzo2 somehow manages to induce
crazy cache thrashing on some CPU models.

Ideas and explanations welcome


Try running single command that is different on different machines under
valgrind (callgrind) on these machines and see that at least number of instructions
executed is the same.

Lzo2 documentation says that there are a lot of algorithms implemented.
It might be choosing the algorithm based on the CPU and the choice it's making might be bad.

Yuri
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