I agree that screensavers are good for marketing. We do get questions about screensavers in forums every now and then so clearly there are people interested in running them.
Sometimes when people upgrade BOINC and see benchmark numbers go up they get excited that now their computer does more work and then we have to explain that "sorry, that's not how it works". I was just curious if this would be the first time when BOINC version actually does make a difference. I didn't think about screensaver going to blank screen after a while. That certainly mitigates any slowdown. -Juha On 13 January 2018 at 03:11, Charlie Fenton <charl...@ssl.berkeley.edu> wrote: > I have not checked task run times. As I understand how the IOSurface APIs > work, once the graphics app has been rebuilt with the latest libraries, it > does not move bitmaps around; it uses the GPU directly and shared memory. > > However, the fallback method I just added is quite inefficient because it > does copy bitmaps in RAM, and so is likely to slow things down. That is why > I initially implemented the IOSurface method. Hopefully, all projects will > upgrade their graphics apps sooner rather than later by relinking with the > new libraries. > > Adding the new fallback method is definitely a tradeoff. As I wrote in the > PR <https://github.com/BOINC/boinc/pull/2294>, I felt that the project > "screensavers" are an important marketing tool. When people see the > graphics on a friend's computer, they can become curious and ask about what > they see, helping spread word of mouth about BOINC And I believe that few > BOINC projects have yet updated their graphics apps to work with the BOINC > screensaver under Mac OS 10.13. I asked David's opinion and he agreed that > I should proceed with this change. > > On versions of OS X older than the latest OS 10.13, there will be no > difference in how the screensaver displays the graphics so there will be no > new effect on CPU caches or task run times. > > Running the screensaver has always had some effect on task run times, > since it is an additional process. That is why the default is to go to a > blank screen after several minutes. > > Cheers, > --Charlie > > > On Jan 12, 2018, at 10:13 AM, Juha Sointusalo <juha.sointus...@gmail.com> > wrote: > > > > On 12 January 2018 at 13:38, Charlie Fenton <charl...@ssl.berkeley.edu> > > wrote: > > > >> This allows older project graphics apps to be displayed by the Mac > >> screensaver under OS 10.13 High Sierra, though at a slower frame rate > than > >> project graphics apps which have been relinked with the BOINC graphics > >> libraries version 7.8.3 or later. The slower frame rate can make > animations > >> appear less smooth. > >> > > > > I don't know how these changes work on the OS side, under the hood. > > Assuming the worst, that this works by copying bitmaps around, I wonder > > what kind of effect this has on task run times. It might not use CPU time > > all that much but it could slow down apps by trashing CPU caches. > > > > Did you happen to check task run times before and after this change? > > > > -Juha > > _______________________________________________ > > boinc_dev mailing list > > boinc_dev@ssl.berkeley.edu > > https://lists.ssl.berkeley.edu/mailman/listinfo/boinc_dev > > To unsubscribe, visit the above URL and > > (near bottom of page) enter your email address. > > > > _______________________________________________ boinc_dev mailing list boinc_dev@ssl.berkeley.edu https://lists.ssl.berkeley.edu/mailman/listinfo/boinc_dev To unsubscribe, visit the above URL and (near bottom of page) enter your email address.
