I think the 2GB "requirement" from Microsoft should be ignored, because plenty of our users are ignoring it.
Nick On Mon, Aug 7, 2017 at 5:51 PM, Chris Peterson <cpeter...@mozilla.com> wrote: > On 2017-08-06 11:26 PM, Henri Sivonen wrote: > >> On Thu, Jul 20, 2017 at 10:42 AM, Chris Peterson<cpeter...@mozilla.com> >> wrote: >> >>> Users with only 2 GB and 5 minute browser sessions would probably have a >>> faster user experience with 32-bit Firefox than with 64-bit, but how do >>> we >>> weigh that experience versus the security benefits of ASLR? >>> >> Not giving users a security mechanism due to a non-obvious reason >> feels bad. Furthermore, considering that Microsoft documents 2 GB as a >> "requirement" for 64-bit Windows, is it really worthwhile for us to >> treat three Windows pointer size combinations (32-bit on 32-bit, >> 64-bit on 64-bit and 32-bit on 64-bit) as fully supported when one of >> the combinations is in contradiction with the OS vendor's stated >> requirements? >> >> Do we have any metrics on whether 32-bit on 64-bit exhibits bugs that >> 32-bit on 32-bit and 64-bit on 64-bit don't? That is, what kind of bug >> burden are we keeping by catering to users who've installed 64-bit >> Windows with less than 2 GB of RAM in contradiction with what >> Microsoft states as a requirement? >> > > That's a fair question. 32-bit applications can only access 2 GB of > virtual address space on Win32 OS, but can access 4 GB on Win64 OS. So in > theory, some 32-bit pointer bugs could manifest differently on Win64 and > Win32. > > Do we test 32-bit Firefox on Win32 or Win64 today? I know we build 32-bit > Firefox on Win64. Since more people will run 32-bit Firefox on Win32 than > on Win64, we should probably test on Win32 or at least test on Win64 > configured to only allow Firefox access to 2 GB of virtual address space. > > In our experiments with Win64 OS users, users with 2 GB or less had > slightly worse retention and crash rates when running 64-bit Firefox than > 32-bit Firefox. > > About 8% of Win64 users in our experiment had 2 GB or less, so we are > talking about choosing a worse user experience for a fair number of people. > (We didn't break out how many users had strictly less than 2 GB.) 64-bit > Chrome's minimum memory requirement is 4 GB, so Google has similarly > decided that supporting 32-bit on Win64 is worth the trouble. > > _______________________________________________ > dev-platform mailing list > dev-platform@lists.mozilla.org > https://lists.mozilla.org/listinfo/dev-platform > _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
