linux/debian/patches/patchset-zen/sauce/0017-ZEN-INTERACTIVE-Tune-ondemand-governor-for-interacti.patch

From e9c6f500f4429c32f583d6da11352b2f0bcce4c8 Mon Sep 17 00:00:00 2001
From: "Jan Alexander Steffens (heftig)" <jan.steffens@gmail.com>
Date: Mon, 27 Jan 2020 18:27:16 +0100
Subject: ZEN: INTERACTIVE: Tune ondemand governor for interactivity

4.10:
During some personal testing with the Dolphin emulator, MuQSS has
serious problems scaling its frequencies causing poor performance where
boosting the CPU frequencies would have fixed them.  Reducing the
up_threshold to 45 with MuQSS appears to fix the issue, letting the
introduction to "Star Wars: Rogue Leader" run at 100% speed versus about
80% on my test system.

Also, lets refactor the definitions and include some indentation to help
the reader discern what the scope of all the macros are.

5.4:
On the last custom kernel benchmark from Phoronix with Xanmod, Michael
configured all the kernels to run using ondemand instead of the kernel's
[default selection][1].  This reminded me that another option outside of
the kernels control is the user's choice to change the cpufreq governor,
for better or for worse.

In Liquorix, performance is the default governor whether you're running
acpi-cpufreq or intel-pstate.  I expect laptop users to install TLP or
LMT to control the power balance on their system, especially when
they're plugged in or on battery.  However, it's pretty clear to me a
lot of people would choose ondemand over performance since it's not
obvious it has huge performance ramifications with MuQSS, and ondemand
otherwise is "good enough" for most people.

Lets codify lower up thresholds for MuQSS to more closely synergize with
its aggressive thread migration behavior.  This way when ondemand is
configured, you get sort of a "performance-lite" type of result but with
the power savings you expect when leaving the running system idle.

[1]: https://www.phoronix.com/scan.php?page=article&item=xanmod-2020-kernel

5.14:
Although CFS and similar schedulers (BMQ, PDS, and CacULE), reuse a lot
more of mainline scheduling and do a good job of pinning single threaded
tasks to their respective core, there's still applications that
confusingly run steady near 50% and benefit from going full speed or
turbo when they need to run (emulators for more recent consoles come to
mind).

Drop the up threshold for all non-MuQSS schedulers from 80/95 to 55/60.

5.15:
Remove MuQSS cpufreq configuration.
---
 drivers/cpufreq/cpufreq_ondemand.c | 8 +++++++-
 init/Kconfig                       | 6 ++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

--- a/drivers/cpufreq/cpufreq_ondemand.c
+++ b/drivers/cpufreq/cpufreq_ondemand.c
@@ -18,10 +18,16 @@
 #include "cpufreq_ondemand.h"
 
 /* On-demand governor macros */
+#if defined(CONFIG_ZEN_INTERACTIVE)
+#define DEF_FREQUENCY_UP_THRESHOLD		(55)
+#define MICRO_FREQUENCY_UP_THRESHOLD		(60)
+#define DEF_SAMPLING_DOWN_FACTOR		(5)
+#else
 #define DEF_FREQUENCY_UP_THRESHOLD		(63)
+#define MICRO_FREQUENCY_UP_THRESHOLD		(70)
 #define DEF_SAMPLING_DOWN_FACTOR		(100)
+#endif
 #define MAX_SAMPLING_DOWN_FACTOR		(100000)
-#define MICRO_FREQUENCY_UP_THRESHOLD		(70)
 #define MIN_FREQUENCY_UP_THRESHOLD		(1)
 #define MAX_FREQUENCY_UP_THRESHOLD		(100)
 
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -166,6 +166,12 @@ config ZEN_INTERACTIVE
 	    Bandwidth slice size...........:   5    ->   3    ms
 	    Task rebalancing threshold.....:  32    ->   8
 
+	  --- CPUFreq Settings -----------------------------------
+
+	    Ondemand sampling down factor..: 100    ->   5
+	    Ondemand default up threshold..:  63    ->  55
+	    Ondemand micro up threshold....:  70    ->  60
+
 config BROKEN
 	bool