diff options
-rw-r--r-- | system/doc/efficiency_guide/advanced.xml | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/system/doc/efficiency_guide/advanced.xml b/system/doc/efficiency_guide/advanced.xml index 3609b8d88e..016302fe50 100644 --- a/system/doc/efficiency_guide/advanced.xml +++ b/system/doc/efficiency_guide/advanced.xml @@ -35,8 +35,7 @@ how much memory different data types and operations require. It is implementation-dependent how much memory the Erlang data types and other items consume, but the following table shows some figures for - the <c>erts-5.2</c> system in R9B. There have been no significant - changes in R13.</p> + the <c>erts-8.0</c> system in OTP 19.0.</p> <p>The unit of measurement is memory words. There exists both a 32-bit and a 64-bit implementation. A word is therefore 4 bytes or @@ -87,6 +86,19 @@ <cell>2 words + the size of each element.</cell> </row> <row> + <cell>Small Map</cell> + <cell>4 words + 2 words per entry (key and value) + the size of each key and value pair.</cell> + </row> + <row> + <cell>Large Map</cell> + <cell> + At least, 2 words + 2 x <c>N</c> words + 2 x log16(<c>N</c>) words + + the size of each key and value pair, where <c>N</c> is the number of pairs in the Map. + A large Map is represented as a tree internally where each node in the tree is a + "sparse tuple" of arity 16. + </cell> + </row> + <row> <cell>Pid</cell> <cell>1 word for a process identifier from the current local node + 5 words for a process identifier from another node.<br></br> @@ -122,7 +134,7 @@ </row> <row> <cell>Erlang process</cell> - <cell>327 words when spawned, including a heap of 233 words.</cell> + <cell>338 words when spawned, including a heap of 233 words.</cell> </row> <tcaption>Memory Size of Different Data Types</tcaption> </table> |