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0 4 GiB VAS 1 |---vvvv-------vvvvvv---vvvv----vv---v----vvv--| mapping |||| |||||| |||| || | ||| file bytes app1 app2 kernel user system_page_file mapping |||| |||||| |||| || | VAS 2
378:
The process then starts executing bytes in the EXE file. However, the only way the process can use or set '-' values in its VAS is to ask the OS to map them to bytes from a file. A common way to use VAS memory in this way is to map it to the
386:
0 4 GiB VAS |---vvv--------vvvvvv---vvvv----vv---v----vvv--| mapping ||| |||||| |||| || | ||| file bytes app kernel user system_page_file
428:, the operating system artificially limits the user mode portion of the process's virtual address space to 2 GiB. This applies to both 32- and 64-bit executables. Processes running executables that were linked with the
375:
0 4 GiB VAS |---vvv--------vvvvvv---vvvv-------------------| mapping ||| |||||| |||| file bytes app kernel user
340:(from 0 to 2 − 1) in that space can have a single byte as a value. Initially, none of them have values ('-' represents no value). Using or setting values in such a VAS would cause a
350:
Then the application's executable file is mapped into the VAS. Addresses in the process VAS are mapped to bytes in the exe file. The OS manages the mapping:
270:
makes available to a process. The range of virtual addresses usually starts at a low address and can extend to the highest address allowed by the computer's
353:
0 4 GiB VAS |---vvv----------------------------------------| mapping ||| file bytes app
409:
are used by the operating system. On later 32-bit editions of
Microsoft Windows, it is possible to extend the user-mode virtual address space to
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is left for kernel-mode virtual address space by marking the programs as IMAGE_FILE_LARGE_ADDRESS_AWARE and enabling the
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establishes the page file as the backing store for any new virtual address space. However, a process can also
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0 4 GiB VAS |----------------------------------------------|
1006:
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383:. The page file is a single file, but multiple distinct sets of contiguous bytes can be mapped into a VAS:
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option, which is the default for 64-bit Visual Studio 2010 and later, have access to more than
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8:
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On
Microsoft Windows 64-bit, in a process running an executable that was linked with
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And different parts of the page file can map into the VAS of different processes:
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files are mapped (this includes custom libraries as well as system ones such as
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OS versions. This provides several benefits, one of which is security through
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32-bit allows splitting the user and kernel address ranges in different ways:
19:"Virtual address" and "virtual addressing" redirect here. For other uses, see
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In the following description, the terminology used will be particular to the
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for 64-bit executables in
Windows through Windows 8, and up to
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are made available to processes for their own use. The other
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operating system, but the concepts are applicable to other
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266:is the set of ranges of virtual addresses that an
448:for 64-bit executables in Windows 8.1 and later.
394:|--------vvvv--vvvvvv---vvvv-------vv---v------|
1274:
278:'s pointer size implementation, which can be 4
733:
674:"/LARGEADDRESSAWARE (Handle Large Addresses)"
654:"/LARGEADDRESSAWARE (Handle Large Addresses)"
614:"/LARGEADDRESSAWARE (Handle Large Addresses)"
195:that contextualizes different points of view.
181:to certain ideas, incidents, or controversies
99:introducing citations to additional sources
588:
586:
60:Learn how and when to remove these messages
740:
726:
298:assuming each process is given a separate
594:"4-Gigabyte Tuning: BCDEdit and Boot.ini"
229:Learn how and when to remove this message
211:Learn how and when to remove this message
583:
240:
89:Relevant discussion may be found on the
1275:
721:
714:" by Jeffrey Richter, Microsoft Press
506:Single address space operating system
356:The v's are values from bytes in the
161:
66:
25:
13:
694:"Linux kernel - x86: Memory split"
329:OS is executed, the process has a
16:Set of ranges of virtual addresses
14:
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41:This article has multiple issues.
436:of virtual address space: up to
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82:relies largely or entirely on a
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30:
21:Virtual address (disambiguation)
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418:
49:or discuss these issues on the
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440:for 32-bit executables, up to
1:
806:Arbitrary-precision or bignum
704:
421:switch in the boot.ini file.
325:When a new application on a
272:instruction set architecture
7:
526:"What is an address space?"
494:
10:
1301:
305:
18:
1180:
1147:Strongly typed identifier
1089:
975:
945:
910:
798:
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401:32-bit, by default, only
571:"LOADED_IMAGE structure"
511:
466:
1222:Parametric polymorphism
634:"Virtual Address Space"
551:"Virtual Address Space"
110:"Virtual address space"
451:Allocating memory via
430:/LARGEADDRESSAWARE:YES
245:
426:/LARGEADDRESSAWARE:NO
336:VAS: each one of the
274:and supported by the
254:virtual address space
244:
189:by rewriting it in a
501:Linear address space
95:improve this article
1227:Primitive data type
1132:Recursive data type
985:Algebraic data type
861:Quadruple precision
1190:Abstract data type
871:Extended precision
830:Reduced precision
320:operating systems.
246:
1270:
1269:
1002:Associative array
866:Octuple precision
489:2G/2G user/kernel
485:1G/3G user/kernel
481:3G/1G user/kernel
399:Microsoft Windows
360:. Then, required
296:process isolation
239:
238:
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175:This article may
160:
159:
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64:
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1242:Type constructor
1127:Opaque data type
1059:Record or Struct
856:Double precision
851:Single precision
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712:Advanced Windows
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187:help improve it
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1200:Data structure
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839:Half precision
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318:virtual memory
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93:. Please help
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1122:Function type
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757:Uninterpreted
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300:address space
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263:address space
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119:
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112: –
111:
107:
106:Find sources:
100:
96:
92:
86:
85:
84:single source
80:This article
78:
74:
69:
68:
63:
61:
54:
53:
48:
47:
42:
37:
28:
27:
22:
1027:Intersection
929:
711:
688:
682:. Microsoft.
677:
668:
662:. Microsoft.
657:
648:
642:. Microsoft.
637:
628:
622:. Microsoft.
617:
608:
602:. Microsoft.
597:
579:. Microsoft.
574:
565:
559:. Microsoft.
554:
545:
533:. Retrieved
529:
520:
488:
484:
480:
470:
463:file bytes.
450:
423:
396:
389:
377:
366:kernel32.dll
355:
349:
324:
311:
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257:
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198:
190:
179:undue weight
176:
148:
138:
131:
124:
117:
105:
81:
57:
50:
44:
43:Please help
40:
1257:Type theory
1252:Type system
1102:Bottom type
1049:Option type
990:generalized
876:Long double
821:Fixed point
483:(default),
413:while only
358:mapped file
201:August 2012
151:August 2012
1162:Empty type
1157:Type class
1107:Collection
1064:Refinement
1042:metaobject
890:signedness
749:Data types
705:References
370:user32.dll
314:Windows NT
121:newspapers
46:improve it
1237:Subtyping
1232:Interface
1215:metaclass
1167:Unit type
1137:Semaphore
1117:Exception
1022:Inductive
1012:Dependent
977:Composite
955:Character
937:Reference
834:Minifloat
790:Bit array
381:page file
250:computing
91:talk page
52:talk page
1277:Category
1262:Variable
1152:Top type
1017:Equality
925:physical
902:Rational
897:Interval
844:bfloat16
495:See also
1205:Generic
1181:Related
1097:Boolean
1054:Product
930:virtual
920:Address
912:Pointer
885:Integer
816:Decimal
811:Complex
799:Numeric
446:128 TiB
306:Example
185:Please
135:scholar
1195:Boxing
1183:topics
1142:Stream
1079:tagged
1037:Object
960:String
535:May 5,
475:CPUs,
457:malloc
327:32-bit
292:64-bit
284:32-bit
137:
130:
123:
116:
108:
1090:Other
1074:Union
1007:Class
997:Array
780:Tryte
512:Notes
477:Linux
467:Linux
442:8 TiB
438:4 GiB
434:2 GiB
415:1 GiB
411:3 GiB
407:2 GiB
403:2 GiB
288:bytes
286:or 8
280:bytes
260:) or
177:lend
142:JSTOR
128:books
1210:Kind
1172:Void
1032:List
947:Text
785:Word
775:Trit
770:Byte
679:MSDN
659:MSDN
639:MSDN
619:MSDN
599:MSDN
576:MSDN
556:MSDN
537:2024
471:For
419:/3GB
368:and
290:for
282:for
252:, a
114:news
1069:Set
765:Bit
530:IBM
487:or
473:x86
455:'s
397:On
372:):
362:DLL
333:GiB
258:VAS
248:In
97:by
1279::
676:.
656:.
636:.
616:.
596:.
585:^
573:.
553:.
528:.
491:.
344:.
331:4
302:.
55:.
741:e
734:t
727:v
710:"
696:.
539:.
453:C
256:(
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226:(
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208:(
203:)
199:(
183:.
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149:(
139:·
132:·
125:·
118:·
101:.
87:.
62:)
58:(
23:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
