diff --git a/arch/i386/Kconfig b/arch/i386/Kconfig index bfdcedef06e1..d4ae5f9ceae6 100644 --- a/arch/i386/Kconfig +++ b/arch/i386/Kconfig @@ -961,6 +961,8 @@ config SECCOMP If unsure, say Y. Only embedded should say N here. +source kernel/Kconfig.hz + endmenu diff --git a/arch/x86_64/Kconfig b/arch/x86_64/Kconfig index 61ed16652347..db259757dc8a 100644 --- a/arch/x86_64/Kconfig +++ b/arch/x86_64/Kconfig @@ -402,6 +402,8 @@ config SECCOMP If unsure, say Y. Only embedded should say N here. +source kernel/Kconfig.hz + endmenu # diff --git a/include/asm-i386/param.h b/include/asm-i386/param.h index b6440526e42a..fa02e67ea86b 100644 --- a/include/asm-i386/param.h +++ b/include/asm-i386/param.h @@ -1,8 +1,10 @@ +#include + #ifndef _ASMi386_PARAM_H #define _ASMi386_PARAM_H #ifdef __KERNEL__ -# define HZ 1000 /* Internal kernel timer frequency */ +# define HZ CONFIG_HZ /* Internal kernel timer frequency */ # define USER_HZ 100 /* .. some user interfaces are in "ticks" */ # define CLOCKS_PER_SEC (USER_HZ) /* like times() */ #endif diff --git a/include/asm-x86_64/param.h b/include/asm-x86_64/param.h index b707f0568c9e..40b11937180d 100644 --- a/include/asm-x86_64/param.h +++ b/include/asm-x86_64/param.h @@ -1,9 +1,11 @@ +#include + #ifndef _ASMx86_64_PARAM_H #define _ASMx86_64_PARAM_H #ifdef __KERNEL__ -# define HZ 1000 /* Internal kernel timer frequency */ -# define USER_HZ 100 /* .. some user interfaces are in "ticks */ +# define HZ CONFIG_HZ /* Internal kernel timer frequency */ +# define USER_HZ 100 /* .. some user interfaces are in "ticks */ #define CLOCKS_PER_SEC (USER_HZ) /* like times() */ #endif diff --git a/kernel/Kconfig.hz b/kernel/Kconfig.hz new file mode 100644 index 000000000000..248e1c396f8b --- /dev/null +++ b/kernel/Kconfig.hz @@ -0,0 +1,46 @@ +# +# Timer Interrupt Frequency Configuration +# + +choice + prompt "Timer frequency" + default HZ_250 + help + Allows the configuration of the timer frequency. It is customary + to have the timer interrupt run at 1000 HZ but 100 HZ may be more + beneficial for servers and NUMA systems that do not need to have + a fast response for user interaction and that may experience bus + contention and cacheline bounces as a result of timer interrupts. + Note that the timer interrupt occurs on each processor in an SMP + environment leading to NR_CPUS * HZ number of timer interrupts + per second. + + + config HZ_100 + bool "100 HZ" + help + 100 HZ is a typical choice for servers, SMP and NUMA systems + with lots of processors that may show reduced performance if + too many timer interrupts are occurring. + + config HZ_250 + bool "250 HZ" + help + 250 HZ is a good compromise choice allowing server performance + while also showing good interactive responsiveness even + on SMP and NUMA systems. + + config HZ_1000 + bool "1000 HZ" + help + 1000 HZ is the preferred choice for desktop systems and other + systems requiring fast interactive responses to events. + +endchoice + +config HZ + int + default 100 if HZ_100 + default 250 if HZ_250 + default 1000 if HZ_1000 +