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==Huge Pages==

Making pages larger means fewer TLB misses for a given TLB size (due to more memory being supportable in the same number of pages, due to narrower page identifiers), large mapping/releasing operations will be faster (due to fewer page table entries needing to be handled), and less memory is devoted to page table entries for a given amount of memory being indexed. The downside is possible wastage of main memory (due to pages not being used as completely). A 2002 paper from Navarro et al at Rice proposed transparent operating system support: "[http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.3.2392 Transparent Operating System Support for Superpages]". Applications must generally be modified or wrapped to take advantage of large pages, for instance on Linux (through at least 2.6.30) and Solaris (through at least Solaris 9); FreeBSD (as of 7.2) claims transparent support with high performance.

Making pages larger means fewer TLB misses for a given TLB size (due to more memory being supportable in the same number of pages, due to narrower page identifiers), large mapping/releasing operations will be faster (due to fewer page table entries needing to be handled), and less memory is devoted to page table entries for a given amount of memory being indexed. The downside is possible wastage of main memory (due to pages not being used as completely), and that disk-backed pages have a larger minimum unit to write out when dirty. A 2002 paper from Navarro et al at Rice proposed transparent operating system support: "[http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.3.2392 Transparent Operating System Support for Superpages]". Applications must generally be modified or wrapped to take advantage of large pages, for instance on Linux (through at least 2.6.30) and Solaris (through at least Solaris 9); FreeBSD (as of 7.2) claims transparent support with high performance.

===Linux===

* They were a [http://lwn.net/Articles/40840/ 2003 Kernel Summit] topic, after seeing first [http://kerneltrap.org/node/418 introduction] in Linux 2.5.36 ([http://linuxgazette.net/155/krishnakumar.html LinuxGazette] primer article)

Pages: Difference between revisions

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 ==Huge Pages==
-Making pages larger means fewer TLB misses for a given TLB size (due to more memory being supportable in the same number of pages, due to narrower page identifiers), large mapping/releasing operations will be faster (due to fewer page table entries needing to be handled), and less memory is devoted to page table entries for a given amount of memory being indexed. The downside is possible wastage of main memory (due to pages not being used as completely). A 2002 paper from Navarro et al at Rice proposed transparent operating system support: "[http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.3.2392 Transparent Operating System Support for Superpages]". Applications must generally be modified or wrapped to take advantage of large pages, for instance on Linux (through at least 2.6.30) and Solaris (through at least Solaris 9); FreeBSD (as of 7.2) claims transparent support with high performance.
+Making pages larger means fewer TLB misses for a given TLB size (due to more memory being supportable in the same number of pages, due to narrower page identifiers), large mapping/releasing operations will be faster (due to fewer page table entries needing to be handled), and less memory is devoted to page table entries for a given amount of memory being indexed. The downside is possible wastage of main memory (due to pages not being used as completely), and that disk-backed pages have a larger minimum unit to write out when dirty. A 2002 paper from Navarro et al at Rice proposed transparent operating system support: "[http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.3.2392 Transparent Operating System Support for Superpages]". Applications must generally be modified or wrapped to take advantage of large pages, for instance on Linux (through at least 2.6.30) and Solaris (through at least Solaris 9); FreeBSD (as of 7.2) claims transparent support with high performance.
 ===Linux===
 * They were a [http://lwn.net/Articles/40840/ 2003 Kernel Summit] topic, after seeing first [http://kerneltrap.org/node/418 introduction] in Linux 2.5.36 ([http://linuxgazette.net/155/krishnakumar.html LinuxGazette] primer article)