Index: en_US.ISO8859-1/books/developers-handbook/newbus/chapter.sgml =================================================================== RCS file: /home/ncvs/doc/en_US.ISO8859-1/books/developers-handbook/newbus/chapter.sgml,v retrieving revision 1.2 diff -u -r1.2 chapter.sgml --- en_US.ISO8859-1/books/developers-handbook/newbus/chapter.sgml 2002/09/08 22:08:56 1.2 +++ en_US.ISO8859-1/books/developers-handbook/newbus/chapter.sgml 2002/10/12 23:27:47 @@ -25,8 +25,9 @@ - Jeroen + Jeroen Ruigrok van der Werven + Asmodai
asmodai@FreeBSD.org
Written by Index: en_US.ISO8859-1/books/developers-handbook/vm/chapter.sgml =================================================================== RCS file: /home/ncvs/doc/en_US.ISO8859-1/books/developers-handbook/vm/chapter.sgml,v retrieving revision 1.3 diff -u -r1.3 chapter.sgml --- en_US.ISO8859-1/books/developers-handbook/vm/chapter.sgml 2002/03/05 15:35:44 1.3 +++ en_US.ISO8859-1/books/developers-handbook/vm/chapter.sgml 2002/10/12 23:27:48 @@ -6,13 +6,20 @@ Virtual Memory System + + Virtual Memory System + + + Matthew + Dillon + +
dillon@FreeBSD.org
+
+
+
+
- - The FreeBSD VM System - - Contributed by &a.dillon;. 6 Feb 1999 - - + Management of physical memory—<literal>vm_page_t</literal> @@ -72,9 +79,9 @@ reactivation page faults to determine how active or how idle a page actually is. This leads to better decisions being made as to when to launder or swap-out a page. - + - + The unified buffer cache—<literal>vm_object_t</literal> @@ -96,9 +103,9 @@ associated with one VM object at a time. The VM object shadowing implements the perceived sharing of the same page across multiple instances. - + - + Filesystem I/O—<literal>struct buf</literal> vnode-backed VM objects, such as file-backed objects, generally @@ -131,9 +138,9 @@ limit the amount of concurrent I/O possible. However, as there are usually a few thousand filesystem buffers available, this is not usually a problem. - + - + Mapping Page Tables - vm_map_t, vm_entry_t FreeBSD separates the physical page table topology from the VM @@ -157,9 +164,9 @@ references to the same page in the same object reference the same vm_page_t and thus give us buffer cache unification across the board. - + - + KVM Memory Mapping FreeBSD uses KVM to hold various kernel structures. The single @@ -179,9 +186,9 @@ constant-sized blocks of memory in order to allocate a specific type of structure. You can use vmstat -m to get an overview of current KVM utilization broken down by zone. - + - + Tuning the FreeBSD VM system A concerted effort has been made to make the FreeBSD kernel @@ -249,7 +256,7 @@ NFS-based swap is perfectly acceptable on -4.x or later systems, but you must be aware that the NFS server will take the brunt of the paging load. - +