From 1e9f28fa1eb9773bf65bae08288c6a0a38eef4a7 Mon Sep 17 00:00:00 2001 From: "Siddha, Suresh B" Date: Mon, 27 Mar 2006 01:15:22 -0800 Subject: [PATCH] sched: new sched domain for representing multi-core Add a new sched domain for representing multi-core with shared caches between cores. Consider a dual package system, each package containing two cores and with last level cache shared between cores with in a package. If there are two runnable processes, with this appended patch those two processes will be scheduled on different packages. On such systems, with this patch we have observed 8% perf improvement with specJBB(2 warehouse) benchmark and 35% improvement with CFP2000 rate(with 2 users). This new domain will come into play only on multi-core systems with shared caches. On other systems, this sched domain will be removed by domain degeneration code. This new domain can be also used for implementing power savings policy (see OLS 2005 CMP kernel scheduler paper for more details.. I will post another patch for power savings policy soon) Most of the arch/* file changes are for cpu_coregroup_map() implementation. Signed-off-by: Suresh Siddha Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/i386/Kconfig | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'arch/i386/Kconfig') diff --git a/arch/i386/Kconfig b/arch/i386/Kconfig index f7db71d0b91..f17bd1d2707 100644 --- a/arch/i386/Kconfig +++ b/arch/i386/Kconfig @@ -231,6 +231,15 @@ config SCHED_SMT cost of slightly increased overhead in some places. If unsure say N here. +config SCHED_MC + bool "Multi-core scheduler support" + depends on SMP + default y + help + Multi-core scheduler support improves the CPU scheduler's decision + making when dealing with multi-core CPU chips at a cost of slightly + increased overhead in some places. If unsure say N here. + source "kernel/Kconfig.preempt" config X86_UP_APIC -- cgit v1.2.3-70-g09d2