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Jun 13, 2022 at 11:27
Encountered a type of bug I've never seen before: upgrading the malloc implementation had a catastrophic effect on performance! I suspect one of my libraries is allocating large arrays and not writing to them.
Fix mimalloc perf regression in 57a4b6d6ce9fb · Wilfred/difftastic@ae42762
Fix mimalloc perf regression in 57a4b6d6ce9fb · Wilfred/difftastic@ae42762
It looks like we were allocating large buffers for wu-diff, and mimalloc performance is much worse for this case in the new version. This reverts performance back to that 0.28 for large files, suc...

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Release 0.68.0 · Wilfred/difftastic
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Do users of immutable systems (i.e Nix or Guix) upgrade more or less often than other platforms? There's less pressure to upgrade (unlike a rolling release distro) but in principle upgrading is easier.