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Diffstat (limited to 'Documentation/sysctl/kernel.txt')
| -rw-r--r-- | Documentation/sysctl/kernel.txt | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt index a4ccdd1981cf..f11ca7979fa6 100644 --- a/Documentation/sysctl/kernel.txt +++ b/Documentation/sysctl/kernel.txt @@ -1,5 +1,6 @@ Documentation for /proc/sys/kernel/* kernel version 2.2.10 (c) 1998, 1999, Rik van Riel <riel@nl.linux.org> + (c) 2009, Shen Feng<shen@cn.fujitsu.com> For general info and legal blurb, please look in README. @@ -18,6 +19,7 @@ Currently, these files might (depending on your configuration) show up in /proc/sys/kernel: - acpi_video_flags - acct +- auto_msgmni - core_pattern - core_uses_pid - ctrl-alt-del @@ -33,6 +35,7 @@ show up in /proc/sys/kernel: - msgmax - msgmnb - msgmni +- nmi_watchdog - osrelease - ostype - overflowgid @@ -40,6 +43,7 @@ show up in /proc/sys/kernel: - panic - pid_max - powersave-nap [ PPC only ] +- panic_on_unrecovered_nmi - printk - randomize_va_space - real-root-dev ==> Documentation/initrd.txt @@ -55,6 +59,7 @@ show up in /proc/sys/kernel: - sysrq ==> Documentation/sysrq.txt - tainted - threads-max +- unknown_nmi_panic - version ============================================================== @@ -381,3 +386,51 @@ can be ORed together: 512 - A kernel warning has occurred. 1024 - A module from drivers/staging was loaded. +============================================================== + +auto_msgmni: + +Enables/Disables automatic recomputing of msgmni upon memory add/remove or +upon ipc namespace creation/removal (see the msgmni description above). +Echoing "1" into this file enables msgmni automatic recomputing. +Echoing "0" turns it off. +auto_msgmni default value is 1. + +============================================================== + +nmi_watchdog: + +Enables/Disables the NMI watchdog on x86 systems. When the value is non-zero +the NMI watchdog is enabled and will continuously test all online cpus to +determine whether or not they are still functioning properly. Currently, +passing "nmi_watchdog=" parameter at boot time is required for this function +to work. + +If LAPIC NMI watchdog method is in use (nmi_watchdog=2 kernel parameter), the +NMI watchdog shares registers with oprofile. By disabling the NMI watchdog, +oprofile may have more registers to utilize. + +============================================================== + +unknown_nmi_panic: + +The value in this file affects behavior of handling NMI. When the value is +non-zero, unknown NMI is trapped and then panic occurs. At that time, kernel +debugging information is displayed on console. + +NMI switch that most IA32 servers have fires unknown NMI up, for example. +If a system hangs up, try pressing the NMI switch. + +============================================================== + +panic_on_unrecovered_nmi: + +The default Linux behaviour on an NMI of either memory or unknown is to continue +operation. For many environments such as scientific computing it is preferable +that the box is taken out and the error dealt with than an uncorrected +parity/ECC error get propogated. + +A small number of systems do generate NMI's for bizarre random reasons such as +power management so the default is off. That sysctl works like the existing +panic controls already in that directory. + |