diff options
Diffstat (limited to 'erts/doc/src/erts_alloc.xml')
| -rw-r--r-- | erts/doc/src/erts_alloc.xml | 42 |
1 files changed, 24 insertions, 18 deletions
diff --git a/erts/doc/src/erts_alloc.xml b/erts/doc/src/erts_alloc.xml index 452e5d990e..86e1e5168a 100644 --- a/erts/doc/src/erts_alloc.xml +++ b/erts/doc/src/erts_alloc.xml @@ -4,7 +4,7 @@ <cref> <header> <copyright> - <year>2002</year><year>2010</year> + <year>2002</year><year>2011</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> @@ -126,9 +126,8 @@ carrier". Main multiblock carriers are never deallocated. The size of the main multiblock carrier is determined by the value of the <seealso marker="#M_mmbcs">mmbcs</seealso> parameter.</p> - <p> <marker id="mseg_mbc_sizes"></marker> - - Sizes of multiblock carriers allocated via <c>mseg_alloc</c> are + <p><marker id="mseg_mbc_sizes"></marker>Sizes of multiblock carriers + allocated via <c>mseg_alloc</c> are decided based on the values of the largest multiblock carrier size (<seealso marker="#M_lmbcs">lmbcs</seealso>), the smallest multiblock carrier size (<seealso marker="#M_smbcs">smbcs</seealso>), @@ -157,9 +156,8 @@ <p>Coalescing of free blocks are always performed immediately. Boundary tags (headers and footers) in free blocks are used which makes the time complexity for coalescing constant.</p> - <p> <marker id="strategy"></marker> - - The memory allocation strategy used for multiblock carriers by an + <p><marker id="strategy"></marker>The memory allocation strategy + used for multiblock carriers by an allocator is configurable via the <seealso marker="#M_as">as</seealso> parameter. Currently the following strategies are available:</p> <taglist> @@ -180,6 +178,14 @@ used. The time complexity is proportional to log N, where N is the number of free blocks.</p> </item> + <tag>Address order first fit</tag> + <item> + <p>Strategy: Find the block with the lowest address that satisfies the + requested block size.</p> + <p>Implementation: A balanced binary search tree is + used. The time complexity is proportional to log N, where + N is the number of free blocks.</p> + </item> <tag>Good fit</tag> <item> <p>Strategy: Try to find the best fit, but settle for the best fit @@ -320,11 +326,11 @@ subsystem identifier, only the specific allocator identified will be effected:</p> <taglist> - <tag><marker id="M_as"><c><![CDATA[+M<S>as bf|aobf|gf|af]]></c></marker></tag> + <tag><marker id="M_as"><c><![CDATA[+M<S>as bf|aobf|aoff|gf|af]]></c></marker></tag> <item> Allocation strategy. Valid strategies are <c>bf</c> (best fit), - <c>aobf</c> (address order best fit), <c>gf</c> (good fit), - and <c>af</c> (a fit). See + <c>aobf</c> (address order best fit), <c>aoff</c> (address order first fit), + <c>gf</c> (good fit), and <c>af</c> (a fit). See <seealso marker="#strategy">the description of allocation strategies</seealso> in "the <c>alloc_util</c> framework" section.</item> <tag><marker id="M_asbcst"><c><![CDATA[+M<S>asbcst <size>]]></c></marker></tag> <item> @@ -437,10 +443,10 @@ in "the <c>alloc_util</c> framework" section.</item> <tag><marker id="M_t"><c><![CDATA[+M<S>t true|false|<amount>]]></c></marker></tag> <item> - Multiple, thread specific instances of the allocator. - This option will only have any effect on the runtime system - with SMP support. Default behaviour on the runtime system with - SMP support (<c>N</c> equals the number of scheduler threads): + <p>Multiple, thread specific instances of the allocator. + This option will only have any effect on the runtime system + with SMP support. Default behaviour on the runtime system with + SMP support (<c>N</c> equals the number of scheduler threads):</p> <taglist> <tag><c>temp_alloc</c></tag> <item><c>N + 1</c> instances.</item> @@ -451,10 +457,10 @@ <c>16</c>. <c>16</c> instances when <c>N</c> is greater than <c>16</c>.</item> </taglist> - <c>temp_alloc</c> will always use <c>N + 1</c> instances when - this option has been enabled regardless of the amount passed. - Other allocators will use the same amount of instances as the - amount passed as long as it isn't greater than <c>N</c>. + <p><c>temp_alloc</c> will always use <c>N + 1</c> instances when + this option has been enabled regardless of the amount passed. + Other allocators will use the same amount of instances as the + amount passed as long as it isn't greater than <c>N</c>.</p> </item> </taglist> <p>Currently the following flags are available for configuration of |