Documentation: incorrect formula to calculate CommitLimit value
PATCH 1/1 Documentation: incorrect formula to calculate CommitLimit value
The formula to calculate "CommitLimit" value mentioned in kernel documentation is incorrect.
Right formula is: CommitLimit = ([total RAM pages] - [total huge TLB pages]) * overcommit_ratio / 100 + [total swap pages]
Signed-off-by Petr Oros <[email protected]>
--- Documentation/filesystems/proc.txt | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
Documentation/filesystems/proc.txt +2 -1
@@ -854,7 +854,8 @@ WritebackTmp: Memory used by FUSE for temporary writeback buffers if strict overcommit accounting is enabled (mode 2 in 'vm.overcommit_memory'). The CommitLimit is calculated with the following formula: - CommitLimit = ('vm.overcommit_ratio' * Physical RAM) + Swap + CommitLimit = ([total RAM pages] - [total huge TLB pages]) * + overcommit_ratio / 100 + [total swap pages] For example, on a system with 1G of physical RAM and 7G of swap with a `vm.overcommit_ratio` of 30 it would yield a CommitLimit of 7.3G.
Signature · 1 line
1.9.0
Quoted 4 lines · Petr Oros
The formula to calculate "CommitLimit" value mentioned in kernel documentation is incorrect.
Right formula is: CommitLimit = ([total RAM pages] - [total huge TLB pages]) *overcommit_ratio/ 100 + [total swap pages]Signed-off-by Petr Oros <[email protected]>
Acked-by Randy Dunlap <[email protected]>
Jiri, please grab this patch.
Thanks.
Quoted 19 lines
--- Documentation/filesystems/proc.txt | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)Documentation/filesystems/proc.txt +2
-1@@ -854,7 +854,8 @@ WritebackTmp: Memory used by FUSE for temporary writeback buffers if strict overcommit accounting is enabled (mode 2 in 'vm.overcommit_memory'). The CommitLimit is calculated with the following formula: - CommitLimit = ('vm.overcommit_ratio' * Physical RAM) + Swap + CommitLimit = ([total RAM pages] - [total huge TLB pages]) * + overcommit_ratio / 100 + [total swap pages] For example, on a system with 1G of physical RAM and 7G of swap with a `vm.overcommit_ratio` of 30 it would yield a CommitLimit of 7.3G.
Signature · 1 line
~Randy