From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Zheng, Qi" Date: Wed, 4 Jul 2018 07:27:08 +0000 Message-ID: <0DD381DBF8F68D419C32ACFCEB28EB2553AEB8B7@SHSMSX101.ccr.corp.intel.com> References: <0DD381DBF8F68D419C32ACFCEB28EB2553ADA8AD@SHSMSX101.ccr.corp.intel.com> In-Reply-To: <0DD381DBF8F68D419C32ACFCEB28EB2553ADA8AD@SHSMSX101.ccr.corp.intel.com> Content-Language: en-US MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Subject: [Xenomai] How to locate the max latency List-Id: Discussions about the Xenomai project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "'xenomai@xenomai.org'" BTW, I already disabled the i915 power saving by adding "i915.enable_dc=3D0= i915.enable_rc6=3D0 i915.enable_execlists=3D0 i915.disable_power_well=3D0"= in the cmdline. Best Regards SSG->OTC->One Linux Platform Engineering Team (Shanghai) From: Zheng, Qi Sent: Tuesday, July 3, 2018 5:00 PM To: xenomai@xenomai.org Subject: How to locate the max latency I am using xenomai 3.0.5 (https://xenomai.org/downloads/xenomai/stable/xeno= mai-3.0.5.tar.bz2) on the Intel SKL platform. On console mode or accessed by vnc viewer (no i915 graphics interrupt), the= max latency values are usually below 20us no matter low or high loading (b= y stress-ng). But the max latency can reach up to 40us on GUI (gnome) mode (dozens of i9= 15 interrupt counts per second). I tried enabling the ipipe trace function, but couldn't find valuable infor= mation. Is there any other good ways to locate the max latency? Or does anybody have experience on reducing the latency caused by graphics = (such as i915) ? Many thanks. Best Regards SSG->OTC->One Linux Platform Engineering Team (Shanghai)