<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_REOPENED " title="REOPENED - [BDW Bisected] OglBatch7 performance reduced by ~7% after enable execlists" href="https://bugs.freedesktop.org/show_bug.cgi?id=87725#c14">Comment # 14</a> on <a class="bz_bug_link bz_status_REOPENED " title="REOPENED - [BDW Bisected] OglBatch7 performance reduced by ~7% after enable execlists" href="https://bugs.freedesktop.org/show_bug.cgi?id=87725">bug 87725</a> from <a class="email" href="mailto:chris@chris-wilson.co.uk" title="Chris Wilson <chris@chris-wilson.co.uk>"> Chris Wilson</a> <pre>It's more or less a fundamental difference in hw implementation between execlists and legacy submission. For whatever reason, execution latency from idle is much worse under execlists, and OglBatch7 hits that path continuously (since the overhead in the driver is sufficient that mesa cannot keep the GPU busy). However, some of this is self inflicted as execlists incurs greater execution overhead, both from per-bb/per-ctx instructions and from being irq driven. Those we can improve and have been improving, but that execution latency is hard to hide.</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> <li>You are the assignee for the bug.</li> <li>You are on the CC list for the bug.</li> </ul> </body> </html>