From 709c1a78cf260618f484c93c17e782387a7bce4a Mon Sep 17 00:00:00 2001 From: Adrian Chadd Date: Mon, 27 Apr 2015 19:18:51 +0000 Subject: [PATCH] Drop the default for performance_cx_lowest (ie, what to use when AC is connected) to ACPI C2. ACPI C3 ends up doing a lot more work before entering sleep, some of which requires grabbing a global ACPI hardware serialising mutex. Because of this, the more CPU cores you have, the more that lock contends under load, reaching close to the #1 lock contention (after VM, which is being worked on.) Tested: * Sandy bridge Xeon, 2 socket * 8 core * Ivy bridge Xeon v2, 2 socket * 8 core * Westmere-EX, 4 socket * 10 core * Ivybridge desktop * Sandybridge mobile * Ivybridge mobile MFC after: 2 weeks --- etc/defaults/rc.conf | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/etc/defaults/rc.conf b/etc/defaults/rc.conf index 2f5cbca5c04f..ef3b8616fabc 100644 --- a/etc/defaults/rc.conf +++ b/etc/defaults/rc.conf @@ -648,7 +648,7 @@ devfs_system_ruleset="" # The name (NOT number) of a ruleset to apply to /dev devfs_set_rulesets="" # A list of /mount/dev=ruleset_name settings to # apply (must be mounted already, i.e. fstab(5)) devfs_load_rulesets="YES" # Enable to always load the default rulesets -performance_cx_lowest="Cmax" # Online CPU idle state +performance_cx_lowest="C2" # Online CPU idle state performance_cpu_freq="NONE" # Online CPU frequency economy_cx_lowest="Cmax" # Offline CPU idle state economy_cpu_freq="NONE" # Offline CPU frequency