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<!DOCTYPE concept
  PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
<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>
</conbody></concept>