發(fā)現(xiàn)有一個(gè)服務(wù)占用大量的內(nèi)存

奇怪的是服務(wù)一開(kāi)始的時(shí)候只占用100M左右內(nèi)存，隨著時(shí)間推移越來(lái)越大，最后導(dǎo)致服務(wù)器內(nèi)存吃緊。這可以算是一種內(nèi)存泄漏的問(wèn)題，之所以標(biāo)題不說(shuō)是內(nèi)存泄漏，最后就會(huì)知道，并不是因?yàn)槭裁礀|西沒(méi)回收導(dǎo)致內(nèi)存泄漏。

于是dump了一下進(jìn)程，使用windbg打開(kāi)后先看看托管堆情況：

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0:000> !eeheap -gc
Number of GC Heaps: 1
generation 0 starts at 0x00000000f2f76a70
generation 1 starts at 0x00000000f2f03400
generation 2 starts at 0x0000000002aa1000
ephemeral segment allocation context: none
???????? segment??????????? begin???????? allocated???????????? size
00000000001a0b80 0000064274e17588? 0000064274e4d910 0x0000000000036388(222088)
00000000001a0990 0000064276928088? 0000064276952e58 0x000000000002add0(175568)
0000000000163cd0 00000642787c3188? 0000064278804c38 0x0000000000041ab0(268976)
0000000002aa0000 0000000002aa1000? 0000000012a9fd70 0x000000000fffed70(268430704)
000000001e280000 000000001e281000? 000000002e26ec58 0x000000000ffedc58(268360792)
000000003b0c0000 000000003b0c1000? 000000004b0ac0f0 0x000000000ffeb0f0(268349680)
000000007fff0000 000000007fff1000? 000000008ffeffb8 0x000000000fffefb8(268431288)
000000008fff0000 000000008fff1000? 000000009ffea648 0x000000000fff9648(268408392)
00000000bfff0000 00000000bfff1000? 00000000cffeffd8 0x000000000fffefd8(268431320)
00000000cfff0000 00000000cfff1000? 00000000dffeffd8 0x000000000fffefd8(268431320)
00000000dfff0000 00000000dfff1000? 00000000effeffb8 0x000000000fffefb8(268431288)
00000000efff0000 00000000efff1000? 00000000f31fecf0 0x000000000320dcf0(52485360)
Large object heap starts at 0x0000000012aa1000
???????? segment??????????? begin???????? allocated???????????? size
0000000012aa0000 0000000012aa1000? 000000001aa9b4f0 0x0000000007ffa4f0(134194416)
000000002fca0000 000000002fca1000? 0000000037c92c88 0x0000000007ff1c88(134159496)
000000004b0c0000 000000004b0c1000? 00000000530a2368 0x0000000007fe1368(134091624)
00000000530c0000 00000000530c1000? 000000005b0bb3f0 0x0000000007ffa3f0(134194160)
0000000068140000 0000000068141000? 00000000701236b8 0x0000000007fe26b8(134096568)
000000009fff0000 000000009fff1000? 00000000a7fd37b0 0x0000000007fe27b0(134096816)
00000000a7ff0000 00000000a7ff1000? 00000000af362700 0x0000000007371700(121050880)
00000000b7ff0000 00000000b7ff1000? 00000000bc1a1260 0x00000000041b0260(68878944)
000000005b0c0000 000000005b0c1000? 000000005f2c1048 0x0000000004200048(69206088)
00000000ffff0000 00000000ffff1000? 0000000107ff1020 0x0000000008000020(134217760)
000000010bff0000 000000010bff1000? 00000001101f1048 0x0000000004200048(69206088)
0000000113ff0000 0000000113ff1000? 000000011bff1020 0x0000000008000020(134217760)
000000011fff0000 000000011fff1000? 00000001241f1048 0x0000000004200048(69206088)
0000000127ff0000 0000000127ff1000? 000000012fff1020 0x0000000008000020(134217760)
0000000133ff0000 0000000133ff1000? 000000013d1f1080 0x0000000009200080(153092224)
000000013fff0000 000000013fff1000? 0000000148229330 0x0000000008238330(136545072)
Total Size??????? 0xf4163e98(4095098520)
------------------------------
GC Heap Size??????? 0xf4163e98(4095098520)

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4G內(nèi)存占用，然后看看哪些對(duì)象最占用內(nèi)存：

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0:000> !dumpheap –stat

00000642788e5b38???? 5168??? 213551344 System.Int32[]
00000642b78659d0???? 2294??? 277543696 System.Data.RBTree`1+Node[[System.Int32, mscorlib]][]
00000642b7820d60???? 2338??? 346840112 System.Data.RBTree`1+Node[[System.Data.DataRow, System.Data]][]
0000000000165b40???? 4000??? 378238288????? Free
00000642788d4758???? 4131??? 675366800 System.Object[]
00000642b77fe7c0? 8667392??? 832069632 System.Data.DataRow
000006427881aaf8 18056660?? 1220045624 System.String

?

其中字符串占用1220MB，DataRow占用832MB，object數(shù)組占用675MB，就這三位大哥加起來(lái)差不多3G了，從什么紅黑樹(shù)結(jié)構(gòu)和DataRow能初步判斷，程序中用到了DataTable，866萬(wàn)行數(shù)據(jù)在內(nèi)存中，再來(lái)算下一個(gè)字符串大概也就占用67字節(jié)，不是很大，這很可能屬于一個(gè)DataRow的列數(shù)據(jù)。隨便選一個(gè)DataRow開(kāi)刀：

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0:000> !dumpheap -mt 00000642b77fe7c0
???????? Address?????????????? MT???? Size
0000000002aa2a68 00000642b77fe7c0?????? 96????
0000000002aa9870 00000642b77fe7c0?????? 96????
0000000002aae0c8 00000642b77fe7c0?????? 96????
0000000002aae1b0 00000642b77fe7c0?????? 96????
0000000002aae290 00000642b77fe7c0?????? 96????
0000000002aae380 00000642b77fe7c0?????? 96????
0000000002aae468 00000642b77fe7c0?????? 96????
0000000002aae550 00000642b77fe7c0?????? 96????
0000000002aae648 00000642b77fe7c0?????? 96????
0000000002aae730 00000642b77fe7c0?????? 96????

?

0:000> !do 0000000002aa2a68
Name: System.Data.DataRow
MethodTable: 00000642b77fe7c0
EEClass: 00000642b781e250
Size: 96(0x60) bytes
(C:\WINDOWS\assembly\GAC_64\System.Data\2.0.0.0__b77a5c561934e089\System.Data.dll)
Fields:
????????????? MT??? Field?? Offset???????????????? Type VT???? Attr??????????? Value Name
00000642b77fcfb0? 40006ad??????? 8 ...em.Data.DataTable? 0 instance 0000000002ab2590 _table
00000642b77ff198? 40006ae?????? 10 ...aColumnCollection? 0 instance 0000000002aad950 _columns
0000064278827060? 40006af?????? 30???????? System.Int32? 0 instance??????????? 31163 oldRecord
0000064278827060? 40006b0?????? 34???????? System.Int32? 0 instance??????????? 31163 newRecord
0000064278827060? 40006b1?????? 38???????? System.Int32? 0 instance?????????????? -1 tempRecord
0000064278827060? 40006b2?????? 3c???????? System.Int32? 0 instance??????????? 31164 _rowID
00000642b7838d00? 40006b3?????? 40???????? System.Int32? 0 instance??????????????? 0 _action
0000064278821048? 40006b4?????? 50?????? System.Boolean? 0 instance??????????????? 0 inChangingEvent
0000064278821048? 40006b5?????? 51?????? System.Boolean? 0 instance??????????????? 0 inDeletingEvent
0000064278821048? 40006b6?????? 52?????? System.Boolean? 0 instance??????????????? 0 inCascade
00000642b77fe2f0? 40006b7?????? 18 ...m.Data.DataColumn? 0 instance 0000000000000000 _lastChangedColumn
0000064278827060? 40006b8?????? 44???????? System.Int32? 0 instance??????????????? 0 _countColumnChange
00000642b78372f8? 40006b9?????? 20 ...em.Data.DataError? 0 instance 0000000000000000 error
0000064278818fb0? 40006ba?????? 28??????? System.Object? 0 instance 0000000000000000 _element
0000064278827060? 40006bb?????? 48???????? System.Int32? 0 instance????????? 3604796 _rbTreeNodeId
0000064278827060? 40006bd?????? 4c???????? System.Int32? 0 instance?????????? 123463 ObjectID
0000064278827060? 40006bc????? 4e8???????? System.Int32? 0?? static????????? 8670024 _objectTypeCount

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這是一個(gè)DataRow，那么我們來(lái)看看這個(gè)DataTable的情況：

0:000> !do 0000000002ab2590
Name: System.Data.DataTable
MethodTable: 00000642b77fcfb0
EEClass: 00000642b781d3b0
Size: 512(0x200) bytes
(C:\WINDOWS\assembly\GAC_64\System.Data\2.0.0.0__b77a5c561934e089\System.Data.dll)
Fields:
????????????? MT??? Field?? Offset???????????????? Type VT???? Attr??????????? Value Name
0000064274e54480? 400099c??????? 8 ...ponentModel.ISite? 0 instance 0000000000000000 site
0000064274e4f1d8? 400099d?????? 10 ....EventHandlerList? 0 instance 0000000000000000 events
0000064278818fb0? 400099b????? 3d0??????? System.Object? 0?? static 0000000000000000 EventDisposed
0000000000000000? 4000732?????? 18? System.Data.DataSet? 0 instance 0000000000000000 dataSet
00000642b77feb30? 4000733?????? 20 System.Data.DataView? 0 instance 0000000000000000 defaultView
0000064278827060? 4000734????? 1a0???????? System.Int32? 0 instance????????? 8575118 nextRowID
00000642b781ec10? 4000735?????? 28 ...DataRowCollection? 0 instance 0000000002aada90 rowCollection
00000642b77ff198? 4000736?????? 30 ...aColumnCollection? 0 instance 0000000002aad950 columnCollection
00000642b781e9d0? 4000737?????? 38 ...straintCollection? 0 instance 0000000002aada30 constraintCollection
0000064278827060? 4000738????? 1a4???????? System.Int32? 0 instance??????????????? 8 elementColumnCount
00000642b7800278? 4000739?????? 40 ...elationCollection? 0 instance 0000000000000000 parentRelationsCollection
00000642b7800278? 400073a?????? 48 ...elationCollection? 0 instance 0000000000000000 childRelationsCollection
00000642b77ff080? 400073b?????? 50 ...ata.RecordManager? 0 instance 0000000002aad7f0 recordManager
0000000000000000? 400073c?????? 58?????????????????????? 0 instance 0000000002aae060 indexes
0000000000000000? 400073d?????? 60?????????????????????? 0 instance 0000000000000000 shadowIndexes
0000064278827060? 400073e????? 1a8???????? System.Int32? 0 instance??????????????? 0 shadowCount
00000642b783bce8? 400073f?????? 68 ...ropertyCollection? 0 instance 0000000000000000 extendedProperties
000006427881aaf8? 4000740?????? 70??????? System.String? 0 instance 0000000002aa4f68 tableName
000006427881aaf8? 4000741?????? 78??????? System.String? 0 instance 0000000000000000 tableNamespace

?

想通過(guò)!objsize看看這個(gè)DataTable的大小，是不是我們找的那個(gè)大家伙，可惜等了一個(gè)小時(shí)也沒(méi)出來(lái)結(jié)果，只能放棄那么有沒(méi)有辦法看到行列數(shù)呢？

?

0:000> !do 0000000002aad950
Name: System.Data.DataColumnCollection
MethodTable: 00000642b77ff198
EEClass: 00000642b788d078
Size: 96(0x60) bytes
(C:\WINDOWS\assembly\GAC_64\System.Data\2.0.0.0__b77a5c561934e089\System.Data.dll)
Fields:
????????????? MT??? Field?? Offset???????????????? Type VT???? Attr??????????? Value Name
0000064274e6d8c8? 400061f????? 220 ...onChangeEventArgs? 0?? static 0000000000000000 RefreshEventArgs
00000642b77fcfb0? 4000675??????? 8 ...em.Data.DataTable? 0 instance 0000000002ab2590 table
000006427883e400? 4000676?????? 10 ...ections.ArrayList? 0 instance 0000000002aad9b0 _list
0000064278827060? 4000677?????? 48???????? System.Int32? 0 instance??????????????? 1 defaultNameIndex
00000642788d4758? 4000678?????? 18????? System.Object[]? 0 instance 0000000000000000 delayedAddRangeColumns
00000642788405d8? 4000679?????? 20 ...ections.Hashtable? 0 instance 0000000002aad9d8 columnFromName
0000064274e67628? 400067a?????? 28 ...hangeEventHandler? 0 instance 0000000000000000 onCollectionChangedDelegate
0000064274e67628? 400067b?????? 30 ...hangeEventHandler? 0 instance 0000000000000000 onCollectionChangingDelegate
0000064274e67628? 400067c?????? 38 ...hangeEventHandler? 0 instance 0000000000000000 onColumnPropertyChangedDelegate
0000064278821048? 400067d?????? 54?????? System.Boolean? 0 instance??????????????? 0 fInClear
00000642788d4758? 400067e?????? 40????? System.Object[]? 0 instance 0000000002ab27a8 columnsImplementingIChangeTracking
0000064278827060? 400067f?????? 4c???????? System.Int32? 0 instance??????????????? 0 nColumnsImplementingIChangeTracking
0000064278827060? 4000680?????? 50???????? System.Int32? 0 instance??????????????? 0 nColumnsImplementingIRevertibleChangeTracking
0:000> !do 0000000002aad9b0
Name: System.Collections.ArrayList
MethodTable: 000006427883e400
EEClass: 0000064278955b38
Size: 40(0x28) bytes
(C:\WINDOWS\assembly\GAC_64\mscorlib\2.0.0.0__b77a5c561934e089\mscorlib.dll)
Fields:
????????????? MT??? Field?? Offset???????????????? Type VT???? Attr??????????? Value Name
00000642788d4758? 4000911??????? 8????? System.Object[]? 0 instance 0000000002b72888 _items
0000064278827060? 4000912?????? 18???????? System.Int32? 0 instance??????????????? 8 _size
0000064278827060? 4000913?????? 1c???????? System.Int32? 0 instance??????????????? 8 _version
0000064278818fb0? 4000914?????? 10??????? System.Object? 0 instance 0000000000000000 _syncRoot
00000642788d4758? 4000915????? 360????? System.Object[]? 0?? shared?????????? static emptyArray
???????????????????????????????? >> Domain:Value? 0000000000160080:0000000002aa1e80 <<
0:000> !do 0000000002b72888
Name: System.Object[]
MethodTable: 00000642788d4758
EEClass: 00000642789d2f80
Size: 96(0x60) bytes
Array: Rank 1, Number of elements 8, Type CLASS
Element Type: System.Object
Fields:
None

?

這里看到了列數(shù)為8，我們選其中一列看看：

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0:000> !do 0000000002b72640
Name: System.Data.DataColumn
MethodTable: 00000642b77fe2f0
EEClass: 00000642b781e198
Size: 232(0xe8) bytes
(C:\WINDOWS\assembly\GAC_64\System.Data\2.0.0.0__b77a5c561934e089\System.Data.dll)
Fields:
????????????? MT??? Field?? Offset???????????????? Type VT???? Attr??????????? Value Name
0000064274e54480? 400099c??????? 8 ...ponentModel.ISite? 0 instance 0000000000000000 site
0000064274e4f1d8? 400099d?????? 10 ....EventHandlerList? 0 instance 0000000000000000 events
0000064278818fb0? 400099b????? 3d0??????? System.Object? 0?? static 0000000000000000 EventDisposed
0000064278821048? 400064c?????? d4?????? System.Boolean? 0 instance??????????????? 1 allowNull
0000064278821048? 400064d?????? d5?????? System.Boolean? 0 instance??????????????? 0 autoIncrement
00000642788272d0? 400064e?????? a0???????? System.Int64? 0 instance 1 autoIncrementStep
00000642788272d0? 400064f?????? a8???????? System.Int64? 0 instance 0 autoIncrementSeed
000006427881aaf8? 4000650?????? 18??????? System.String? 0 instance 0000000000000000 caption
000006427881aaf8? 4000651?????? 20??????? System.String? 0 instance 0000000002b62fd0 _columnName
000006427882a650? 4000652?????? 28????????? System.Type? 0 instance 0000000002ab6fe0 dataType
0000064278818fb0? 4000653?????? 30??????? System.Object? 0 instance 0000000002ad8ac0 defaultValue
00000642b7839b30? 4000654?????? b8???????? System.Int32? 0 instance??????????????? 3 _dateTimeMode
00000642b7800ab0? 4000655?????? 38 ...ta.DataExpression? 0 instance 0000000000000000 expression
0000064278827060? 4000656?????? bc???????? System.Int32? 0 instance?????????????? 32 maxLength
0000064278827060? 4000657?????? c0???????? System.Int32? 0 instance??????????????? 3 _ordinal
0000064278821048? 4000658?????? d6?????? System.Boolean? 0 instance??????????????? 0 readOnly
00000642b77ff4a0? 4000659?????? 40??? System.Data.Index? 0 instance 0000000000000000 sortIndex
00000642b77fcfb0? 400065a?????? 48 ...em.Data.DataTable? 0 instance 0000000002ab2590 table
0000064278821048? 400065b?????? d7?????? System.Boolean? 0 instance??????????????? 0 unique
00000642b783b5e0? 400065c?????? c4???????? System.Int32? 0 instance??????????????? 1 columnMapping
0000064278827060? 400065d?????? c8???????? System.Int32? 0 instance??????????????? 0 _hashCode
0000064278827060? 400065e?????? cc???????? System.Int32? 0 instance??????????????? 0 errors
0000064278821048? 400065f?????? d8?????? System.Boolean? 0 instance??????????????? 0 isSqlType
0000064278821048? 4000660?????? d9?????? System.Boolean? 0 instance??????????????? 0 implementsINullable
0000064278821048? 4000661?????? da?????? System.Boolean? 0 instance??????????????? 0 implementsIChangeTracking
0000064278821048? 4000662?????? db?????? System.Boolean? 0 instance??????????????? 0 implementsIRevertibleChangeTracking
0000064278821048? 4000663?????? dc?????? System.Boolean? 0 instance??????????????? 0 implementsIXMLSerializable
0000064278821048? 4000664?????? dd?????? System.Boolean? 0 instance??????????????? 1 defaultValueIsNull
0000000000000000? 4000665?????? 50?????????????????????? 0 instance 0000000000000000 dependentColumns
00000642b783bce8? 4000666?????? 58 ...ropertyCollection? 0 instance 0000000000000000 extendedProperties
0000064274e862f8? 4000667?????? 60 ...angedEventHandler? 0 instance 0000000000000000 onPropertyChangingDelegate
00000642b77f7070? 4000668?????? 68 ...ommon.DataStorage? 0 instance 0000000002b735f8 _storage
00000642788272d0? 4000669?????? b0???????? System.Int64? 0 instance 0 autoIncrementCurrent
000006427881aaf8? 400066a?????? 70??????? System.String? 0 instance 0000000000000000 _columnUri
000006427881aaf8? 400066b?????? 78??????? System.String? 0 instance 0000000002aa4f68 _columnPrefix
000006427881aaf8? 400066c?????? 80??????? System.String? 0 instance 0000000000000000 encodedColumnName
000006427881aaf8? 400066d?????? 88??????? System.String? 0 instance 0000000002aa4f68 description
000006427881aaf8? 400066e?????? 90??????? System.String? 0 instance 0000000002aa4f68 dttype
00000642b77ffaa0? 400066f?????? 98 ...m.Data.SimpleType? 0 instance 0000000002b72728 simpleType
0000064278827060? 4000671?????? d0???????? System.Int32? 0 instance?????????????? 35 _objectID
0000064278827060? 4000670????? 4d0???????? System.Int32? 0?? static??????????? 10254 _objectTypeCount
0:000> !do 0000000002b62fd0
Name: System.String
MethodTable: 000006427881aaf8
EEClass: 000006427892f7d8
Size: 36(0x24) bytes
(C:\WINDOWS\assembly\GAC_64\mscorlib\2.0.0.0__b77a5c561934e089\mscorlib.dll)
String: mapid
Fields:
????????????? MT??? Field?? Offset???????????????? Type VT???? Attr??????????? Value Name
0000064278827060? 4000096??????? 8???????? System.Int32? 0 instance??????????????? 6 m_arrayLength
0000064278827060? 4000097??????? c???????? System.Int32? 0 instance??????????????? 5 m_stringLength
00000642788216d8? 4000098?????? 10????????? System.Char? 0 instance?????????????? 6d m_firstChar
000006427881aaf8? 4000099?????? 20??????? System.String? 0?? shared?????????? static Empty
???????????????????????????????? >> Domain:Value? 0000000000160080:00000642787c36e0 <<
00000642788db830? 400009a?????? 28??????? System.Char[]? 0?? shared?????????? static WhitespaceChars
???????????????????????????????? >> Domain:Value? 0000000000160080:0000000002aa14e8 <<

?

看到了，這列叫mapid，有多少行？

?

0:000> !do 0000000002b735f8
Name: System.Data.Common.StringStorage
MethodTable: 00000642b781f218
EEClass: 00000642b788db20
Size: 80(0x50) bytes
(C:\WINDOWS\assembly\GAC_64\System.Data\2.0.0.0__b77a5c561934e089\System.Data.dll)
Fields:
????????????? MT??? Field?? Offset???????????????? Type VT???? Attr??????????? Value Name
00000642b77fe2f0? 4000aab??????? 8 ...m.Data.DataColumn? 0 instance 0000000002b72640 Column
00000642b77fcfb0? 4000aac?????? 10 ...em.Data.DataTable? 0 instance 0000000002ab2590 Table
000006427882a650? 4000aad?????? 18????????? System.Type? 0 instance 0000000002ab6fe0 DataType
00000642b783f6a8? 4000aae?????? 38???????? System.Int32? 0 instance?????????????? 18 StorageTypeCode
000006427883f8d8? 4000aaf?????? 20 ...lections.BitArray? 0 instance 0000000000000000 dbNullBits
0000064278818fb0? 4000ab0?????? 28??????? System.Object? 0 instance 00000642787c36e0 DefaultValue
0000064278818fb0? 4000ab1?????? 30??????? System.Object? 0 instance 0000000002ad8ac0 NullValue
0000064278821048? 4000ab2?????? 3c?????? System.Boolean? 0 instance??????????????? 0 IsCloneable
0000064278821048? 4000ab3?????? 3d?????? System.Boolean? 0 instance??????????????? 0 IsCustomDefinedType
0000064278821048? 4000ab4?????? 3e?????? System.Boolean? 0 instance??????????????? 1 IsStringType
0000064278821048? 4000ab5?????? 3f?????? System.Boolean? 0 instance??????????????? 0 IsValueType
00000642788d4758? 4000aaa????? 330????? System.Object[]? 0?? static 0000000002b64da0 StorageClassType
00000642788d4758? 4000c26?????? 40????? System.Object[]? 0 instance 0000000113ff1000 values
0:000> !do 0000000113ff1000
Name: System.Object[]
MethodTable: 00000642788d4758
EEClass: 00000642789d2f80
Size: 134217760(0x8000020) bytes
Array: Rank 1, Number of elements 16777216, Type CLASS
Element Type: System.String
Fields:
None

?

天哪，1600多萬(wàn)行，64位機(jī)器指針8字節(jié)，光指針占用134MB，別說(shuō)里面的字符串了。那么基本可以確定這就是罪魁禍?zhǔn)琢恕，F(xiàn)在問(wèn)題就是想看看里面的數(shù)據(jù)，那么隨便輸出幾個(gè)：

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0:000> !dumparray -length 10 -details 0000000113ff1000
Name: System.String[]
MethodTable: 00000642788d4758
EEClass: 00000642789d2f80
Size: 134217760(0x8000020) bytes
Array: Rank 1, Number of elements 16777216, Type CLASS
Element Methodtable: 000006427881aaf8
[0] 0000000002b731c0
??? Name: System.String
??? MethodTable: 000006427881aaf8
??? EEClass: 000006427892f7d8
??? Size: 90(0x5a) bytes
???? (C:\WINDOWS\assembly\GAC_64\mscorlib\2.0.0.0__b77a5c561934e089\mscorlib.dll)
??? String:???? e51ff7d827024ea1981f7c3a754d6b80???
??? Fields:
????????????????? MT??? Field?? Offset???????????????? Type VT???? Attr??????????? Value Name
??? 0000064278827060? 4000096??????? 8???????? System.Int32? 0 instance?????????????? 33 m_arrayLength
??? 0000064278827060? 4000097??????? c???????? System.Int32? 0 instance?????????????? 32 m_stringLength
??? 00000642788216d8? 4000098?????? 10????????? System.Char? 0 instance?????????????? 65 m_firstChar
??? 000006427881aaf8? 4000099?????? 20??????? System.String? 0?? shared?????????? static Empty
???????????????????????????????? >> Domain:Value? 0000000000160080:00000642787c36e0 <<
??? 00000642788db830? 400009a?????? 28??????? System.Char[]? 0?? shared?????????? static WhitespaceChars
???????????????????????????????? >> Domain:Value? 0000000000160080:0000000002aa14e8 <<
[1] 0000000002b73890
??? Name: System.String
??? MethodTable: 000006427881aaf8
??? EEClass: 000006427892f7d8
??? Size: 90(0x5a) bytes
???? (C:\WINDOWS\assembly\GAC_64\mscorlib\2.0.0.0__b77a5c561934e089\mscorlib.dll)
??? String:???? e5296215c29c4c2e97079b4d33357f1d???
??? Fields:
????????????????? MT??? Field?? Offset???????????????? Type VT???? Attr??????????? Value Name
??? 0000064278827060? 4000096??????? 8???????? System.Int32? 0 instance?????????????? 33 m_arrayLength
??? 0000064278827060? 4000097??????? c???????? System.Int32? 0 instance?????????????? 32 m_stringLength
??? 00000642788216d8? 4000098?????? 10????????? System.Char? 0 instance?????????????? 65 m_firstChar
??? 000006427881aaf8? 4000099?????? 20??????? System.String? 0?? shared?????????? static Empty
???????????????????????????????? >> Domain:Value? 0000000000160080:00000642787c36e0 <<
??? 00000642788db830? 400009a?????? 28??????? System.Char[]? 0?? shared?????????? static WhitespaceChars
???????????????????????????????? >> Domain:Value? 0000000000160080:0000000002aa14e8 <<
[2] 0000000002b73978
??? Name: System.String
??? MethodTable: 000006427881aaf8
??? EEClass: 000006427892f7d8
??? Size: 90(0x5a) bytes
???? (C:\WINDOWS\assembly\GAC_64\mscorlib\2.0.0.0__b77a5c561934e089\mscorlib.dll)
??? String:???? 7afb5e8ccefd4b5fb0a251efaec1356a???
??? Fields:
????????????????? MT??? Field?? Offset???????????????? Type VT???? Attr??????????? Value Name
??? 0000064278827060? 4000096??????? 8???????? System.Int32? 0 instance?????????????? 33 m_arrayLength
??? 0000064278827060? 4000097??????? c???????? System.Int32? 0 instance?????????????? 32 m_stringLength
??? 00000642788216d8? 4000098?????? 10????????? System.Char? 0 instance?????????????? 37 m_firstChar
??? 000006427881aaf8? 4000099?????? 20??????? System.String? 0?? shared?????????? static Empty
???????????????????????????????? >> Domain:Value? 0000000000160080:00000642787c36e0 <<
??? 00000642788db830? 400009a?????? 28??????? System.Char[]? 0?? shared?????????? static WhitespaceChars
???????????????????????????????? >> Domain:Value? 0000000000160080:0000000002aa14e8 <<
[3] 0000000002b73a58
??? Name: System.String
??? MethodTable: 000006427881aaf8
??? EEClass: 000006427892f7d8
??? Size: 90(0x5a) bytes
???? (C:\WINDOWS\assembly\GAC_64\mscorlib\2.0.0.0__b77a5c561934e089\mscorlib.dll)
??? String:???? 844faa0f6f5e407cae6d9f5dc7cead4f???
??? Fields:
????????????????? MT??? Field?? Offset???????????????? Type VT???? Attr??????????? Value Name
??? 0000064278827060? 4000096??????? 8???????? System.Int32? 0 instance?????????????? 33 m_arrayLength
??? 0000064278827060? 4000097??????? c???????? System.Int32? 0 instance?????????????? 32 m_stringLength
??? 00000642788216d8? 4000098?????? 10????????? System.Char? 0 instance?????????????? 38 m_firstChar
??? 000006427881aaf8? 4000099?????? 20??????? System.String? 0?? shared?????????? static Empty
???????????????????????????????? >> Domain:Value? 0000000000160080:00000642787c36e0 <<
??? 00000642788db830? 400009a?????? 28??????? System.Char[]? 0?? shared?????????? static WhitespaceChars
???????????????????????????????? >> Domain:Value? 0000000000160080:0000000002aa14e8 <<
[4] 0000000002b73b38
??? Name: System.String
??? MethodTable: 000006427881aaf8
??? EEClass: 000006427892f7d8
??? Size: 90(0x5a) bytes
???? (C:\WINDOWS\assembly\GAC_64\mscorlib\2.0.0.0__b77a5c561934e089\mscorlib.dll)
??? String:???? 35c966ae4fd445c2b1bae15d6ae4b940???
??? Fields:
????????????????? MT??? Field?? Offset???????????????? Type VT???? Attr??????????? Value Name
??? 0000064278827060? 4000096??????? 8???????? System.Int32? 0 instance?????????????? 33 m_arrayLength
??? 0000064278827060? 4000097??????? c???????? System.Int32? 0 instance?????????????? 32 m_stringLength
??? 00000642788216d8? 4000098?????? 10????????? System.Char? 0 instance?????????????? 33 m_firstChar
??? 000006427881aaf8? 4000099?????? 20??????? System.String? 0?? shared?????????? static Empty
???????????????????????????????? >> Domain:Value? 0000000000160080:00000642787c36e0 <<
??? 00000642788db830? 400009a?????? 28??????? System.Char[]? 0?? shared?????????? static WhitespaceChars
???????????????????????????????? >> Domain:Value? 0000000000160080:0000000002aa14e8 <<
[5] 0000000002b73c18
??? Name: System.String
??? MethodTable: 000006427881aaf8
??? EEClass: 000006427892f7d8
??? Size: 90(0x5a) bytes
???? (C:\WINDOWS\assembly\GAC_64\mscorlib\2.0.0.0__b77a5c561934e089\mscorlib.dll)
??? String:???? cc09aef8fb314933b557758bc7d29f98???
??? Fields:
????????????????? MT??? Field?? Offset???????????????? Type VT???? Attr??????????? Value Name
??? 0000064278827060? 4000096??????? 8???????? System.Int32? 0 instance?????????????? 33 m_arrayLength
??? 0000064278827060? 4000097??????? c???????? System.Int32? 0 instance?????????????? 32 m_stringLength
??? 00000642788216d8? 4000098?????? 10????????? System.Char? 0 instance?????????????? 63 m_firstChar
??? 000006427881aaf8? 4000099?????? 20??????? System.String? 0?? shared?????????? static Empty
???????????????????????????????? >> Domain:Value? 0000000000160080:00000642787c36e0 <<
??? 00000642788db830? 400009a?????? 28??????? System.Char[]? 0?? shared?????????? static WhitespaceChars
???????????????????????????????? >> Domain:Value? 0000000000160080:0000000002aa14e8 <<
[6] 0000000002b73cf8
??? Name: System.String
??? MethodTable: 000006427881aaf8
??? EEClass: 000006427892f7d8
??? Size: 90(0x5a) bytes
???? (C:\WINDOWS\assembly\GAC_64\mscorlib\2.0.0.0__b77a5c561934e089\mscorlib.dll)
??? String:???? dd60b243d07f4cffa8e61cccb668fe9e???
??? Fields:
????????????????? MT??? Field?? Offset???????????????? Type VT???? Attr??????????? Value Name
??? 0000064278827060? 4000096??????? 8???????? System.Int32? 0 instance?????????????? 33 m_arrayLength
??? 0000064278827060? 4000097??????? c???????? System.Int32? 0 instance?????????????? 32 m_stringLength
??? 00000642788216d8? 4000098?????? 10????????? System.Char? 0 instance?????????????? 64 m_firstChar
??? 000006427881aaf8? 4000099?????? 20??????? System.String? 0?? shared?????????? static Empty
???????????????????????????????? >> Domain:Value? 0000000000160080:00000642787c36e0 <<
??? 00000642788db830? 400009a?????? 28??????? System.Char[]? 0?? shared?????????? static WhitespaceChars
???????????????????????????????? >> Domain:Value? 0000000000160080:0000000002aa14e8 <<
[7] 0000000002b73de0
??? Name: System.String
??? MethodTable: 000006427881aaf8
??? EEClass: 000006427892f7d8
??? Size: 90(0x5a) bytes
???? (C:\WINDOWS\assembly\GAC_64\mscorlib\2.0.0.0__b77a5c561934e089\mscorlib.dll)
??? String:???? eab4d9ebf4d54e1e9bc020fc36700745???
??? Fields:
????????????????? MT??? Field?? Offset???????????????? Type VT???? Attr??????????? Value Name
??? 0000064278827060? 4000096??????? 8???????? System.Int32? 0 instance?????????????? 33 m_arrayLength
??? 0000064278827060? 4000097??????? c???????? System.Int32? 0 instance?????????????? 32 m_stringLength
??? 00000642788216d8? 4000098?????? 10????????? System.Char? 0 instance?????????????? 65 m_firstChar
??? 000006427881aaf8? 4000099?????? 20??????? System.String? 0?? shared?????????? static Empty
???????????????????????????????? >> Domain:Value? 0000000000160080:00000642787c36e0 <<
??? 00000642788db830? 400009a?????? 28??????? System.Char[]? 0?? shared?????????? static WhitespaceChars
???????????????????????????????? >> Domain:Value? 0000000000160080:0000000002aa14e8 <<
[8] 0000000002b73fc8
??? Name: System.String
??? MethodTable: 000006427881aaf8
??? EEClass: 000006427892f7d8
??? Size: 90(0x5a) bytes
???? (C:\WINDOWS\assembly\GAC_64\mscorlib\2.0.0.0__b77a5c561934e089\mscorlib.dll)
??? String:???? 71117207efb3410298384554834dc389???
??? Fields:
????????????????? MT??? Field?? Offset???????????????? Type VT???? Attr??????????? Value Name
??? 0000064278827060? 4000096??????? 8???????? System.Int32? 0 instance?????????????? 33 m_arrayLength
??? 0000064278827060? 4000097??????? c???????? System.Int32? 0 instance?????????????? 32 m_stringLength
??? 00000642788216d8? 4000098?????? 10????????? System.Char? 0 instance?????????????? 37 m_firstChar
??? 000006427881aaf8? 4000099?????? 20??????? System.String? 0?? shared?????????? static Empty
???????????????????????????????? >> Domain:Value? 0000000000160080:00000642787c36e0 <<
??? 00000642788db830? 400009a?????? 28??????? System.Char[]? 0?? shared?????????? static WhitespaceChars
???????????????????????????????? >> Domain:Value? 0000000000160080:0000000002aa14e8 <<
[9] 0000000002b740b0
??? Name: System.String
??? MethodTable: 000006427881aaf8
??? EEClass: 000006427892f7d8
??? Size: 90(0x5a) bytes
???? (C:\WINDOWS\assembly\GAC_64\mscorlib\2.0.0.0__b77a5c561934e089\mscorlib.dll)
??? String:???? 3c54a40a97ab4d4aa5fdaaeeefa903c1???
??? Fields:
????????????????? MT??? Field?? Offset???????????????? Type VT???? Attr??????????? Value Name
??? 0000064278827060? 4000096??????? 8???????? System.Int32? 0 instance?????????????? 33 m_arrayLength
??? 0000064278827060? 4000097??????? c???????? System.Int32? 0 instance?????????????? 32 m_stringLength
??? 00000642788216d8? 4000098?????? 10????????? System.Char? 0 instance?????????????? 33 m_firstChar
??? 000006427881aaf8? 4000099?????? 20??????? System.String? 0?? shared?????????? static Empty
???????????????????????????????? >> Domain:Value? 0000000000160080:00000642787c36e0 <<
??? 00000642788db830? 400009a?????? 28??????? System.Char[]? 0?? shared?????????? static WhitespaceChars
???????????????????????????????? >> Domain:Value? 0000000000160080:0000000002aa14e8 <<

?

好像都是一些md5后的字符串，現(xiàn)在的工作就是到代碼中找DataTable了，看到：

?

SqlDataReader sqlDataReader = db.GetReader("select * from typetable");
??????????? ddd.Load(sqlDataReader);

?

這個(gè)ddd的DataTable很可疑，因?yàn)閷?duì)照數(shù)據(jù)庫(kù)中的表看到這個(gè)表有8列：

?

并且其中也有一個(gè)mapid，那么看看mapid的數(shù)據(jù)：

差不多是這個(gè)，那么就是它了，但一看數(shù)據(jù)量：

才2萬(wàn)多，怎么內(nèi)存里有千萬(wàn)數(shù)據(jù)？？

之后通過(guò)探查其它列的數(shù)據(jù)發(fā)現(xiàn)這里面數(shù)據(jù)都是重復(fù)的，說(shuō)明有重復(fù)加載，查找所有和ddd相關(guān)的代碼：

只有3個(gè)地方往里面加數(shù)據(jù)，首先懷疑ddd.Rows.Add，但是后來(lái)查看發(fā)現(xiàn)只有在數(shù)據(jù)行不存在的情況下才會(huì)加，難道是Load方法？第一Load方法是在程序啟動(dòng)的時(shí)候一次性加載的，而第二個(gè)是在業(yè)務(wù)邏輯中做的，查看了一下MSDN傻眼了，由于ddd是靜態(tài)變量，Load方法每一次都會(huì)根據(jù)主鍵檢查行是否存在，如果不存在的話(huà)作為新行，因此ddd就不斷重復(fù)加2萬(wàn)多行，導(dǎo)致。。。。

做一個(gè)實(shí)驗(yàn)：

using (SqlConnection conn = new SqlConnection(""))
??????????? {
??????????????? conn.Open();
??????????????? using (SqlCommand cmd = new SqlCommand("select * from typetable", conn))
??????????????? {
??????????????????? using (SqlDataReader reader = cmd.ExecuteReader())
??????????????????? {
??????????????????????? typetable.Load(reader);
??????????????????? }
??????????????? }
??????????? }

??????????? MessageBox.Show(typetable.Rows.Count.ToString());

?

?

第一次運(yùn)行，程序很愉快的輸出了：

再按一次按鈕：

?

果然這樣，那么嘗試把第一列設(shè)置為主鍵試試：

if (typetable.Columns.Count > 0)
{
??? typetable.PrimaryKey = new DataColumn[] { typetable.Columns[0] };
}

經(jīng)過(guò)試驗(yàn)，問(wèn)題得到解決。好了，程序中問(wèn)題找到了，解決辦法也有了，接下去就是修改驗(yàn)證的過(guò)程了。

感覺(jué)這應(yīng)該不算內(nèi)存泄漏的問(wèn)題，而是作者沒(méi)有意識(shí)到DataTable的Load方法在沒(méi)指明主鍵的時(shí)候作為新行來(lái)處理：

?

Load 方法的此版本嘗試保留每行中的當(dāng)前值，使原始值保持不變。（如果要更精細(xì)地控制傳入數(shù)據(jù)的行為，請(qǐng)參見(jiàn) DataTable.Load 方法。）如果現(xiàn)有的行和傳入的行包含對(duì)應(yīng)的主鍵值，將使用其當(dāng)前行狀態(tài)值來(lái)處理行，否則將該行視為新行。

轉(zhuǎn)載于:https://www.cnblogs.com/lovecindywang/archive/2010/06/18/1760099.html

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