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<concept id="GUID-763A2636-D448-5353-9E31-F61FE7EB39DA" xml:lang="en"><title>Flat

or segmented buffer?</title><shortdesc>Describes the occasions you should choose a flat buffer and when

to choose a segmented buffers.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

<p>The choice between using an array implemented with a flat buffer against

using an array implemented with a segmented buffer depends on the characteristics

of the application.</p>

<p>Choose a flat buffer:</p>

<ul>

<li id="GUID-0FC7D827-EA67-598C-8DE6-91860661DA7C"><p>if efficiency in transforming

between buffer position and memory address is very important.</p> </li>

<li id="GUID-73802049-15D7-550A-8093-87BF3CA2E387"><p>if the re-allocations

needed to extend the buffer are sufficiently rare that they do not cause intolerable

amounts of data copying or heap fragmentation.</p> </li>

<li id="GUID-2129EE71-7859-5B77-91FD-F036348C92D6"><p>if there is an upper

bound on the size limit and can reserve sufficient room before inserting elements.</p> </li>

</ul>

<p>Choose a segmented buffer:</p>

<ul>

<li id="GUID-912802E0-C66D-56F1-9977-6B04BFD833AC"><p>to minimise the heap

thrashing and copying that can be associated with reallocating

a single flat buffer.</p> </li>

<li id="GUID-CE5DB4C3-BC72-5D09-B55A-552D08CB8EF6"><p>if the performance of

frequent insertions and deletions is a concern. This can be better with segmented

buffers, because not all data after the insertion/deletion point needs to

be shuffled to complete the operation.</p> </li>

</ul>