<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - [SKL dmc] Headless mode media transcoding is 20-30% slower comparing to connected monitor use case" href="https://bugs.freedesktop.org/show_bug.cgi?id=100572#c22">Comment # 22</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - [SKL dmc] Headless mode media transcoding is 20-30% slower comparing to connected monitor use case" href="https://bugs.freedesktop.org/show_bug.cgi?id=100572">bug 100572</a> from <a class="email" href="mailto:sunil.kamath@intel.com" title="Sunil Kamath <sunil.kamath@intel.com>"> Sunil Kamath</a> <pre>>> Some details and further tests to be tried are: >> >> Though by avoiding DMC fw load, issue is going away issue is not lilted just >> to DMC fw. (proved by other tests results) > >Which results are you referring to? So far I haven't been able to reproduce the performance regression without the DMC loaded. But yeah, it is possible it >is an driver - firmware interaction of some sorts. I am referring to results with “i915.disable_power_wells=0”. > >> Real way to address this is to gracefully handle power infra change for a >> headless system. >> >> “i915.disable_power_wells=0” fixes performance issue on DP too? > >It fixes the issue in headless mode and headless mode cannot have DP connected so not sure what you mean by this? Here im referring to <a href="show_bug.cgi?id=100572#c19">comment #19</a>. If the same scenario is tested with i915.disable_power_wells=0. But I got further clarity in below comments from you. > >What Dmitry observed in #19 is that forcing the DP connector on hasn't got the same workaround effect as forcing the HDMI on does. As far as I could see, >there is some difference in the display code paths, where forcing the DP on does not actually turn on the power well(s). Contrary to forcing the HDMI >connector to on which does this. There is also a difference in system behaviour depending on presence or absence of fbcon, but this is just a secondary >effect of modeset happening or not when the connector is forced. This is the area where I was seeking efforts from Imre – to clarify further on power infrastructure handling for headless-system.</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the assignee for the bug.</li> <li>You are the QA Contact for the bug.</li> <li>You are on the CC list for the bug.</li> </ul> </body> </html>