diff options
author | Hiroki Sato <hrs@FreeBSD.org> | 2009-04-30 21:20:09 +0000 |
---|---|---|
committer | Hiroki Sato <hrs@FreeBSD.org> | 2009-04-30 21:20:09 +0000 |
commit | 510c6cf29a128c3504341a84ee778f6ce9de01d1 (patch) | |
tree | d71318275812c9ae3148e3d9c1bd303eae8b5c75 | |
parent | c998438538bcb6edcac132db994a82fd851f3e44 (diff) |
Notes
-rw-r--r-- | release/doc/en_US.ISO8859-1/relnotes/article.sgml | 19 |
1 files changed, 10 insertions, 9 deletions
diff --git a/release/doc/en_US.ISO8859-1/relnotes/article.sgml b/release/doc/en_US.ISO8859-1/relnotes/article.sgml index cde6e6215b1a..37aeb3069362 100644 --- a/release/doc/en_US.ISO8859-1/relnotes/article.sgml +++ b/release/doc/en_US.ISO8859-1/relnotes/article.sgml @@ -296,15 +296,16 @@ <literal>VFS_AIO</literal>.</para> <para arch="amd64,i386">The &os; virtual memory subsystem now - supports <application>Superpages</application>. The - <application>Superpages</application> is a feature that - enables each entry in the TLB (translation lookaside buffer) - to map a large physical memory region into a virtual address - space in modern CPUs. This provides possible memory savings - for applications that share large amounts of memory between - the address spaces and performance improvements due to fewer - TLB misses. This is disabled by default and can be enabled by - setting a loader tunable + supports fully transparent use of + <application>superpages</application> for application memory; + application memory pages are dynamically promoted to or + demoted from superpages without any modification to + application code. This change offers the benefit of large + page sizes such as improved virtual memory efficiency and + reduced TLB (translation lookaside buffer) misses without + downsides like application changes and virtual memory + inflexibility. This is disabled by default and can be enabled + by setting a loader tunable <varname>vm.pmap.pg_ps_enabled</varname> to <literal>1</literal>.</para> |