alt Hacker NewsNotably windows doesn't use overcommit, and degrades much more gracefully under memory pressure. The biggest tradeoff is the amount of disk space consumed by a page file that also has to reserve space for unused pages that have been allocated but never been swapped in. On linux you can turn overcommit off, but there's too much software written around the assumption that overcommit is on
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fc417fc802 • today at 9:47 AM
Is that still the case today? Notably (IIUC) overcommit is required for certain security measures. I believe it was chromium that I noticed mmaping somewhere north of 1 TB of memory on startup so that it can do (again IIUC) something akin to ASLR internally.
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Windows also does a neat trick Linux lacks: automatically adding more swap, up to a limit. Systems with loads of RAM barely lose any storage to swap, but once they do get hit, they can get many gigabytes of swap space without user interaction. I believe macOS does it too, of course.
I'm sure there are many reasons why Linux can't do that by default, but it's a real shame.