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-rw-r--r--community/gsoc/project_ideas.mdwn1
-rw-r--r--community/gsoc/project_ideas/physical_memory_management.mdwn51
2 files changed, 0 insertions, 52 deletions
diff --git a/community/gsoc/project_ideas.mdwn b/community/gsoc/project_ideas.mdwn
index 7338d57..4993b01 100644
--- a/community/gsoc/project_ideas.mdwn
+++ b/community/gsoc/project_ideas.mdwn
@@ -102,7 +102,6 @@ project_ideas:
community/gsoc/project_ideas/package_manager
community/gsoc/project_ideas/xattr
community/gsoc/project_ideas/driver_glue_code
- community/gsoc/project_ideas/physical_memory_management
community/gsoc/project_ideas/language_bindings
community/gsoc/project_ideas/file_locking
community/gsoc/project_ideas/gdb
diff --git a/community/gsoc/project_ideas/physical_memory_management.mdwn b/community/gsoc/project_ideas/physical_memory_management.mdwn
deleted file mode 100644
index 1bb6a76..0000000
--- a/community/gsoc/project_ideas/physical_memory_management.mdwn
+++ /dev/null
@@ -1,51 +0,0 @@
-[[!meta copyright="Copyright © 2015, 2016 Free Software Foundation, Inc."]]
-
-[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable
-id="license" text="Permission is granted to copy, distribute and/or modify this
-document under the terms of the GNU Free Documentation License, Version 1.2 or
-any later version published by the Free Software Foundation; with no Invariant
-Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license
-is included in the section entitled
-[[GNU Free Documentation License|/fdl]]."]]"""]]
-
-[[!meta title="Physical memory management"]]
-
-GNU Mach is currently suffering from severe limitations caused by the way
-it manages physical memory. For example, since it requires pages to be mapped
-in kernel space in order to be used, the maximum amount of usable physical
-memory is currently around 800MB (or 1.8GB if a 2/2 split is set). And
-because the page allocator is unable to easily return blocks of contiguous
-pages, the kernel has to use virtual memory to provide contiguity.
-But the kernel virtual space is separate from the direct mapping of
-physical memory, so the larger it is, the less physical pages available.
-The size of the kernel space is currently around 200MB, with around 100MB
-for kernel objects. This small size prevents the system from achieving
-scalability, since a panic occurs when the kernel is unable to allocate
-a kernel object such as a port. In addition, the kernel uses mainly tables
-to store IPC rights. When a table is full, it is enlarged through a kernel
-specific version of realloc(). When a file system starts managing many
-files (e.g. because some of their content is cached in physical memory),
-these tables can get big enough to make realloc() fail because of
-fragmentation.
-
-The goal of this project is to make as much physical memory available as
-possible for both the kernel and applications, by rewriting the page
-allocator into a buddy allocator to support contiguous block allocations,
-using it directly instead of virtual memory as the backend of the slab
-allocator for kernel objects, and, if time allows it, transform IPC right
-tables (e.g. into radix trees) and get rid of realloc().
-
-This project requires a good understanding of virtual memory (both physical
-mappings at the MMU level and virtual mappings at the VM level), and strong
-skills in C programming. Note that some work has already been done in the
-X15 project about this, and can be reused as a reference.
-
-Useful links :
-
- * <https://www.sceen.net/mapping-physical-memory-directly/>
-
- * <http://git.sceen.net/rbraun/x15.git/>
-
- * <https://git.sceen.net/rbraun/librbraun.git/plain/rdxtree.h>
-
-Possible mentors: Richard Braun