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Bug ID: JDK-6347833 (fs) Enhance MappedByteBuffer to support sizes >2GB on 64 bit platforms
JDK-6347833 : (fs) Enhance MappedByteBuffer to support sizes >2GB on 64 bit platforms

Details
Type:
Enhancement
Submit Date:
2005-11-09
Status:
Closed
Updated Date:
2011-02-16
Project Name:
JDK
Resolved Date:
2010-08-31
Component:
core-libs
OS:
linux
Sub-Component:
java.nio
CPU:
x86
Priority:
P5
Resolution:
Future Project
Affected Versions:
1.4.2,5.0
Fixed Versions:

Related Reports
Relates:
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Sub Tasks

Description
A DESCRIPTION OF THE REQUEST :
The current implementation of MappedByteBuffer imposes a 2GB maximum size limit even on 64 bit machines with operating systems and physical memory that could support larger sizes.

JUSTIFICATION :
The 2GB limit prevents Java applications calling MappedByteBuffer from taking advantage of the large memory available on 64 bit platforms.

                                    

Comments
EVALUATION

A MappedByteBuffer is a ByteBuffer with additional operations to support memory-mapped file regions. To support mapping a region larger than Integer.MAX_VALUE would require a parallel hierarchy of classes. For now the only solution is create multiple MappedByteBuffers where each corresponds to a region that is no larger than 2GB.
                                     
2005-11-09



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