On Tue, Oct 27, 2009 at 10:35 PM, Adam Barth <[email protected]> wrote:
> On Tue, Oct 27, 2009 at 10:27 PM, Darin Fisher <[email protected]> wrote: > > What version of Windows are you using? I find the double-buffering on > Vista > > and Win7 to have a big negative impact on performance as compared to > WinXP. > > I'm always delighted to run Chrome on my old WinXP laptop. It seems so > > much faster there. > > I lied. I actually have four laptops. So both Vista and XP. > However, the Vista one has worse specs so I wasn't counting it. > > > On X-windows, the renderer backingstores are managed by the X server, and > > the transport DIBs are also managed by the X server. So, we avoid a lot > of > > memcpy costs incurred on Windows due to keeping the backingstores in main > > memory there. > > We don't draw into a device dependent bitmap on Windows? Is that not > similar? I was wondering if core IPC latency was lower on Linux. > That number bleeds into a lot of other times. > We do not. We once did, but DDBs are a very limited resource on Windows. They get charged against the desktop process, and if you exceed the seemingly artificial cap, then the system will start having serious problems. New apps will fail to run properly. No remote desktop for you, etc. So, we switched away from DDBs and just use DIBs. (We use a pixel depth to match your display--kind of.) > > > I suspect this is at least one of the bigger issues. > > I also suspect that process creation is a problem on Windows. We should > > probably look into having a spare child process on Windows to minimize > new > > tab jank. Maybe there is a bug on this already? > > If we're not doing that already, that seems like it might be a big win. > We are most definitely not doing that yet. We could also just move process creation to a background thread. An unused process might just get swapped out and be no cheaper to "make live" than it would be to create a new process. -Darin --~--~---------~--~----~------------~-------~--~----~ Chromium Developers mailing list: [email protected] View archives, change email options, or unsubscribe: http://groups.google.com/group/chromium-dev -~----------~----~----~----~------~----~------~--~---
