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-rw-r--r--Documentation/sysctl/kernel.txt26
-rw-r--r--Documentation/sysctl/net.txt16
-rw-r--r--Documentation/sysctl/vm.txt14
3 files changed, 42 insertions, 14 deletions
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index 6fccb69c0..f1a8333dd 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -38,6 +38,7 @@ show up in /proc/sys/kernel:
- hung_task_timeout_secs
- hung_task_warnings
- kexec_load_disabled
+- iso_cpu
- kptr_restrict
- kstack_depth_to_print [ X86 only ]
- l2cr [ PPC only ]
@@ -66,6 +67,7 @@ show up in /proc/sys/kernel:
- randomize_va_space
- real-root-dev ==> Documentation/initrd.txt
- reboot-cmd [ SPARC only ]
+- rr_interval
- rtsig-max
- rtsig-nr
- sem
@@ -384,6 +386,16 @@ kernel stack.
==============================================================
+iso_cpu: (BFS CPU scheduler only).
+
+This sets the percentage cpu that the unprivileged SCHED_ISO tasks can
+run effectively at realtime priority, averaged over a rolling five
+seconds over the -whole- system, meaning all cpus.
+
+Set to 70 (percent) by default.
+
+==============================================================
+
l2cr: (PPC only)
This flag controls the L2 cache of G3 processor boards. If
@@ -723,6 +735,20 @@ rebooting. ???
==============================================================
+rr_interval: (BFS CPU scheduler only)
+
+This is the smallest duration that any cpu process scheduling unit
+will run for. Increasing this value can increase throughput of cpu
+bound tasks substantially but at the expense of increased latencies
+overall. Conversely decreasing it will decrease average and maximum
+latencies but at the expense of throughput. This value is in
+milliseconds and the default value chosen depends on the number of
+cpus available at scheduler initialisation with a minimum of 6.
+
+Valid values are from 1-1000.
+
+==============================================================
+
rtsig-max & rtsig-nr:
The file rtsig-max can be used to tune the maximum number
diff --git a/Documentation/sysctl/net.txt b/Documentation/sysctl/net.txt
index 6294b5186..809ab6efc 100644
--- a/Documentation/sysctl/net.txt
+++ b/Documentation/sysctl/net.txt
@@ -54,13 +54,15 @@ default_qdisc
--------------
The default queuing discipline to use for network devices. This allows
-overriding the default queue discipline of pfifo_fast with an
-alternative. Since the default queuing discipline is created with the
-no additional parameters so is best suited to queuing disciplines that
-work well without configuration like stochastic fair queue (sfq),
-CoDel (codel) or fair queue CoDel (fq_codel). Don't use queuing disciplines
-like Hierarchical Token Bucket or Deficit Round Robin which require setting
-up classes and bandwidths.
+overriding the default of pfifo_fast with an alternative. Since the default
+queuing discipline is created without additional parameters so is best suited
+to queuing disciplines that work well without configuration like stochastic
+fair queue (sfq), CoDel (codel) or fair queue CoDel (fq_codel). Don't use
+queuing disciplines like Hierarchical Token Bucket or Deficit Round Robin
+which require setting up classes and bandwidths. Note that physical multiqueue
+interfaces still use mq as root qdisc, which in turn uses this default for its
+leaves. Virtual devices (like e.g. lo or veth) ignore this setting and instead
+default to noqueue.
Default: pfifo_fast
busy_read
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index 9832ec52f..a4482fcea 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -225,11 +225,11 @@ with your system. To disable them, echo 4 (bit 3) into drop_caches.
extfrag_threshold
This parameter affects whether the kernel will compact memory or direct
-reclaim to satisfy a high-order allocation. /proc/extfrag_index shows what
-the fragmentation index for each order is in each zone in the system. Values
-tending towards 0 imply allocations would fail due to lack of memory,
-values towards 1000 imply failures are due to fragmentation and -1 implies
-that the allocation will succeed as long as watermarks are met.
+reclaim to satisfy a high-order allocation. The extfrag/extfrag_index file in
+debugfs shows what the fragmentation index for each order is in each zone in
+the system. Values tending towards 0 imply allocations would fail due to lack
+of memory, values towards 1000 imply failures are due to fragmentation and -1
+implies that the allocation will succeed as long as watermarks are met.
The kernel will not compact memory in a zone if the
fragmentation index is <= extfrag_threshold. The default value is 500.
@@ -349,7 +349,7 @@ zone[i]'s protection[j] is calculated by following expression.
(i < j):
zone[i]->protection[j]
- = (total sums of present_pages from zone[i+1] to zone[j] on the node)
+ = (total sums of managed_pages from zone[i+1] to zone[j] on the node)
/ lowmem_reserve_ratio[i];
(i = j):
(should not be protected. = 0;
@@ -360,7 +360,7 @@ The default values of lowmem_reserve_ratio[i] are
256 (if zone[i] means DMA or DMA32 zone)
32 (others).
As above expression, they are reciprocal number of ratio.
-256 means 1/256. # of protection pages becomes about "0.39%" of total present
+256 means 1/256. # of protection pages becomes about "0.39%" of total managed
pages of higher zones on the node.
If you would like to protect more pages, smaller values are effective.