On Mon, Feb 4, 2013 at 11:23 PM, Asa Dotzler <a...@mozilla.com> wrote: > On 2/4/2013 6:59 PM, Dave Mandelin wrote: >> I was talking to Taras and Naveed about this today, and what also >> came up was: >> >> 4. Do the work to make 64-bit JS jit perf as good as 32-bit JS jit >> perf, and then switch to x64 builds for Windows. There are of course >> many issues involved with such a switch, > > (These numbers are somewhat crude. I don't have excel on this machine to do > precise math from our blocklist data. Given my somewhat dated info on the > Windows 32 vs 64 bit breakdown that level of precision isn't really > warranted.) > > Approximately 35% of our installs are on Windows XP. Microsoft has said that > less than 1% of XP installs are 64-bit. About 7% of our users are on Vista. > Microsoft said Vista's 64-bit percentage is about 11%. Just over 50% of our > Windows users are on Windows 7. Microsoft has said Windows 7 installs are > about 50% 32-bit and 50% 64-bit. That puts 32-bit Windows Firefox users at > around 65% of our total Windows user base. > > With nearly two thirds of our Windows users on 32-bit Windows versions, we > can't simply "switch to x64 builds for Windows" can we?
Definitely not. Thanks for reminding me. I guess there is still an option of trying to do PGO on 64-bit builds only (which apparently is definitely not possible for VS2010 and earlier) and letting more users pick up those benefits over time. But that's not very compelling. Dave _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
