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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2016-05-09 09:39:13 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2016-05-09 09:39:13 +0200
commit10ee08292028d3d22d201a34ba7d24a085818cb3 (patch)
treecf3bff48a7eab154574355f00a4b4f27dc85ff11 /Documentation/sysctl/vm.txt
parent7da4b8b7378790dd1e4af1bb7522863127fa1438 (diff)
parent44549e8f5eea4e0a41b487b63e616cb089922b99 (diff)
Merge 4.6-rc7 into tty-next
We want the pty fixes in here as well so that patches can build on it. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation/sysctl/vm.txt')
-rw-r--r--Documentation/sysctl/vm.txt19
1 files changed, 10 insertions, 9 deletions
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index cb0368459da3..34a5fece3121 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -581,15 +581,16 @@ Specify "[Nn]ode" for node order
"Zone Order" orders the zonelists by zone type, then by node within each
zone. Specify "[Zz]one" for zone order.
-Specify "[Dd]efault" to request automatic configuration. Autoconfiguration
-will select "node" order in following case.
-(1) if the DMA zone does not exist or
-(2) if the DMA zone comprises greater than 50% of the available memory or
-(3) if any node's DMA zone comprises greater than 70% of its local memory and
- the amount of local memory is big enough.
-
-Otherwise, "zone" order will be selected. Default order is recommended unless
-this is causing problems for your system/application.
+Specify "[Dd]efault" to request automatic configuration.
+
+On 32-bit, the Normal zone needs to be preserved for allocations accessible
+by the kernel, so "zone" order will be selected.
+
+On 64-bit, devices that require DMA32/DMA are relatively rare, so "node"
+order will be selected.
+
+Default order is recommended unless this is causing problems for your
+system/application.
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