First: I did say "Beyond those guesses,". The information provided by the OP so far consists solely of the build parameters for the two builds. I compared those two sets and attempted to reason about possibilities.

A non-problem that allows you to trivially DoS any web server where input from the client

Hm. That problem was addressed way back in 2003/5.8.1 with something akin to this:

<Reveal this spoiler or all in this thread>

So what new problem was addressed by the 5.17 changes? (And has anyone ever seen a plausible demonstration of that "new problem"? Has there ever been a reported sighting of anyone exploiting that new problem in the field? If the change is so critical, why wasn't it back-ported to 5.10 and other earlier versions that are still being shipped with 95% of *nix distributions?)

Anyway, perl's hash handling has been getting faster, not slower in recent years.

Agreed. Not just hash handling, but just about every aspect of Perl (save maybe string handling) has gotten faster in recent builds. Congratulations.

However, over the years there have been some weird behaviours that only affected windows builds.

Once again I'll remind you that I was attempting to help the OP on the basis of the minimal information supplied; whilst asking him to provide more.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority". The enemy of (IT) success is complexity.
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^5: Our perl/xs/c app is 30% slower with 64bit 5.24.0, than with 32bit 5.8.9. Why? by BrowserUk
in thread Our perl/xs/c app is 30% slower with 64bit 5.24.0, than with 32bit 5.8.9. Why? by Anonymous Monk

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