Messages in this thread Patch in this message | | | From | Raghavendra K T <> | Subject | [PATCH] x86 kconfig: Add recommendation to enable paravirt spinlock | Date | Mon, 21 Oct 2013 21:35:08 +0530 |
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Since paravirt spinlock optimization are in 3.12 kernel, we have very good performance benefit for paravirtualized KVM / Xen kernel. Also we no longer suffer from 5% side effect on native kernel.
Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> --- Would like to thank Sander for spotting and suggesting this. pvspinlock benefit on KVM link: https://lkml.org/lkml/2013/8/6/178 Attilio's tests on native kernel impact: http://blog.xen.org/index.php/2012/05/11/benchmarking-the-new-pv-ticketlock-implementation/
arch/x86/Kconfig | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index f67e839..4ba9d32 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -638,10 +638,10 @@ config PARAVIRT_SPINLOCKS spinlock implementation with something virtualization-friendly (for example, block the virtual CPU rather than spinning). - Unfortunately the downside is an up to 5% performance hit on - native kernels, with various workloads. + It has minimal impact on native kernels and gives nice performance + benefit for paravirtualized KVM / Xen kernels. - If you are unsure how to answer this question, answer N. + If you are unsure how to answer this question, answer Y. source "arch/x86/xen/Kconfig" -- 1.7.11.7
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