diff options
Diffstat (limited to 'Documentation/admin-guide')
-rw-r--r-- | Documentation/admin-guide/bootconfig.rst | 11 | ||||
-rw-r--r-- | Documentation/admin-guide/cgroup-v2.rst | 4 | ||||
-rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 36 | ||||
-rw-r--r-- | Documentation/admin-guide/sysctl/kernel.rst | 3 | ||||
-rw-r--r-- | Documentation/admin-guide/sysctl/vm.rst | 15 |
5 files changed, 50 insertions, 19 deletions
diff --git a/Documentation/admin-guide/bootconfig.rst b/Documentation/admin-guide/bootconfig.rst index d6b3b77a4129..a22024f9175e 100644 --- a/Documentation/admin-guide/bootconfig.rst +++ b/Documentation/admin-guide/bootconfig.rst @@ -71,6 +71,16 @@ For example,:: foo = bar, baz foo = qux # !ERROR! we can not re-define same key +If you want to update the value, you must use the override operator +``:=`` explicitly. For example:: + + foo = bar, baz + foo := qux + +then, the ``qux`` is assigned to ``foo`` key. This is useful for +overriding the default value by adding (partial) custom bootconfigs +without parsing the default bootconfig. + If you want to append the value to existing key as an array member, you can use ``+=`` operator. For example:: @@ -84,6 +94,7 @@ For example, following config is NOT allowed.:: foo = value1 foo.bar = value2 # !ERROR! subkey "bar" and value "value1" can NOT co-exist + foo.bar := value2 # !ERROR! even with the override operator, this is NOT allowed. Comments diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst index fa4018afa5a4..6be43781ec7f 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -1274,6 +1274,10 @@ PAGE_SIZE multiple when read back. Amount of memory used for storing in-kernel data structures. + percpu + Amount of memory used for storing per-cpu kernel + data structures. + sock Amount of memory used in network transmission buffers diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 98ea67f27809..bdc1f33fd3d1 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -724,7 +724,7 @@ memory region [offset, offset + size] for that kernel image. If '@offset' is omitted, then a suitable offset is selected automatically. - [KNL, x86_64] select a region under 4G first, and + [KNL, X86-64] Select a region under 4G first, and fall back to reserve region above 4G when '@offset' hasn't been specified. See Documentation/admin-guide/kdump/kdump.rst for further details. @@ -737,14 +737,14 @@ Documentation/admin-guide/kdump/kdump.rst for an example. crashkernel=size[KMG],high - [KNL, x86_64] range could be above 4G. Allow kernel + [KNL, X86-64] range could be above 4G. Allow kernel to allocate physical memory region from top, so could be above 4G if system have more than 4G ram installed. Otherwise memory region will be allocated below 4G, if available. It will be ignored if crashkernel=X is specified. crashkernel=size[KMG],low - [KNL, x86_64] range under 4G. When crashkernel=X,high + [KNL, X86-64] range under 4G. When crashkernel=X,high is passed, kernel could allocate physical memory region above 4G, that cause second kernel crash on system that require some amount of low memory, e.g. swiotlb @@ -1427,7 +1427,7 @@ gamma= [HW,DRM] - gart_fix_e820= [X86_64] disable the fix e820 for K8 GART + gart_fix_e820= [X86-64] disable the fix e820 for K8 GART Format: off | on default: on @@ -1814,7 +1814,7 @@ Format: 0 | 1 Default set by CONFIG_INIT_ON_FREE_DEFAULT_ON. - init_pkru= [x86] Specify the default memory protection keys rights + init_pkru= [X86] Specify the default memory protection keys rights register contents for all processes. 0x55555554 by default (disallow access to all but pkey 0). Can override in debugfs after boot. @@ -1822,7 +1822,7 @@ inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver Format: <irq> - int_pln_enable [x86] Enable power limit notification interrupt + int_pln_enable [X86] Enable power limit notification interrupt integrity_audit=[IMA] Format: { "0" | "1" } @@ -1840,7 +1840,7 @@ bypassed by not enabling DMAR with this option. In this case, gfx device will use physical address for DMA. - forcedac [x86_64] + forcedac [X86-64] With this option iommu will not optimize to look for io virtual address below 32-bit forcing dual address cycle on pci bus for cards supporting greater @@ -1925,7 +1925,7 @@ strict regions from userspace. relaxed - iommu= [x86] + iommu= [X86] off force noforce @@ -1935,8 +1935,8 @@ merge nomerge soft - pt [x86] - nopt [x86] + pt [X86] + nopt [X86] nobypass [PPC/POWERNV] Disable IOMMU bypass, using IOMMU for PCI devices. @@ -2079,21 +2079,21 @@ iucv= [HW,NET] - ivrs_ioapic [HW,X86_64] + ivrs_ioapic [HW,X86-64] Provide an override to the IOAPIC-ID<->DEVICE-ID mapping provided in the IVRS ACPI table. For example, to map IOAPIC-ID decimal 10 to PCI device 00:14.0 write the parameter as: ivrs_ioapic[10]=00:14.0 - ivrs_hpet [HW,X86_64] + ivrs_hpet [HW,X86-64] Provide an override to the HPET-ID<->DEVICE-ID mapping provided in the IVRS ACPI table. For example, to map HPET-ID decimal 0 to PCI device 00:14.0 write the parameter as: ivrs_hpet[0]=00:14.0 - ivrs_acpihid [HW,X86_64] + ivrs_acpihid [HW,X86-64] Provide an override to the ACPI-HID:UID<->DEVICE-ID mapping provided in the IVRS ACPI table. For example, to map UART-HID:UID AMD0020:0 to @@ -2370,7 +2370,7 @@ lapic [X86-32,APIC] Enable the local APIC even if BIOS disabled it. - lapic= [x86,APIC] "notscdeadline" Do not use TSC deadline + lapic= [X86,APIC] "notscdeadline" Do not use TSC deadline value for LAPIC timer one-shot implementation. Default back to the programmable timer unit in the LAPIC. @@ -3188,12 +3188,12 @@ register save and restore. The kernel will only save legacy floating-point registers on task switch. - nohugeiomap [KNL,x86,PPC] Disable kernel huge I/O mappings. + nohugeiomap [KNL,X86,PPC] Disable kernel huge I/O mappings. nosmt [KNL,S390] Disable symmetric multithreading (SMT). Equivalent to smt=1. - [KNL,x86] Disable symmetric multithreading (SMT). + [KNL,X86] Disable symmetric multithreading (SMT). nosmt=force: Force disable SMT, cannot be undone via the sysfs control file. @@ -3955,7 +3955,7 @@ pt. [PARIDE] See Documentation/admin-guide/blockdev/paride.rst. - pti= [X86_64] Control Page Table Isolation of user and + pti= [X86-64] Control Page Table Isolation of user and kernel address spaces. Disabling this feature removes hardening, but improves performance of system calls and interrupts. @@ -3967,7 +3967,7 @@ Not specifying this option is equivalent to pti=auto. - nopti [X86_64] + nopti [X86-64] Equivalent to pti=off pty.legacy_count= diff --git a/Documentation/admin-guide/sysctl/kernel.rst b/Documentation/admin-guide/sysctl/kernel.rst index 2ae9669eb22c..d4b32cc32bb7 100644 --- a/Documentation/admin-guide/sysctl/kernel.rst +++ b/Documentation/admin-guide/sysctl/kernel.rst @@ -164,7 +164,8 @@ core_pattern %s signal number %t UNIX time of dump %h hostname - %e executable filename (may be shortened) + %e executable filename (may be shortened, could be changed by prctl etc) + %f executable filename %E executable path %c maximum size of core file by resource limit RLIMIT_CORE %<OTHER> both are dropped diff --git a/Documentation/admin-guide/sysctl/vm.rst b/Documentation/admin-guide/sysctl/vm.rst index d997cc3c26d0..4b9d2e8e9142 100644 --- a/Documentation/admin-guide/sysctl/vm.rst +++ b/Documentation/admin-guide/sysctl/vm.rst @@ -119,6 +119,21 @@ all zones are compacted such that free memory is available in contiguous blocks where possible. This can be important for example in the allocation of huge pages although processes will also directly compact memory as required. +compaction_proactiveness +======================== + +This tunable takes a value in the range [0, 100] with a default value of +20. This tunable determines how aggressively compaction is done in the +background. Setting it to 0 disables proactive compaction. + +Note that compaction has a non-trivial system-wide impact as pages +belonging to different processes are moved around, which could also lead +to latency spikes in unsuspecting applications. The kernel employs +various heuristics to avoid wasting CPU cycles if it detects that +proactive compaction is not being effective. + +Be careful when setting it to extreme values like 100, as that may +cause excessive background compaction activity. compact_unevictable_allowed =========================== |