Core Data 抛出 NSInternalInconsistencyException “100 次尝试后上下文仍然很脏。”

Posted 2023-03-05

【中文标题】Core Data 抛出 NSInternalInconsistencyException “100 次尝试后上下文仍然很脏。”

【英文标题】：Core Data throws NSInternalInconsistencyException "The context is still dirty after 100 attempts."

【发布时间】：2012-02-02 09:00:24

【问题描述】：

我很难找到以下异常的原因。它不时发生，没有明确的模式我可以重复重现问题。

Terminating app due to uncaught exception 'NSInternalInconsistencyException',
reason: 'Failed to process pending changes before save. 
The context is still dirty after 100 attempts. 
Typically this recursive dirtying is caused by a bad validation method, 
-willSave, or notification handler.'

应用程序存储和处理跟踪数据并且只处理一个实体：

@interface CSTrackingEntry : NSManagedObject
  @property (nonatomic, retain) NSString * data;
  @property (nonatomic, retain) NSDate * dateRecorded;
@end

CSTracking 条目是批量读取、创建和删除的。几到几十个，每几分钟一次。没有注册通知处理程序。

更新：堆栈捕获

2012-02-03 10:26:11.121 BatteryNurse[17162:1803] An uncaught exception was raised
2012-02-03 10:26:11.121 BatteryNurse[17162:1803] Failed to process pending changes 
before save.  The context is still dirty after 100 attempts.  Typically this recursive 
dirtying is caused by a bad validation method, -willSave, or notification handler.
2012-02-03 10:26:11.264 BatteryNurse[17162:1803] *** Terminating app due to uncaught 
exception 'NSInternalInconsistencyException', reason: 'Failed to process pending changes 
before save.  The context is still dirty after 100 attempts.  Typically this recursive 
dirtying is caused by a bad validation method, -willSave, or notification handler.'
*** Call stack at first throw:
(
0   CoreFoundation                      0x00007fff8183f784 __exceptionPreprocess + 180
1   libobjc.A.dylib                     0x00007fff89306f03 objc_exception_throw + 45
2   CoreData                            0x00007fff8543a654 -[NSManagedObjectContext(_NSInternalChangeProcessing) _prepareForPushChanges:] + 244
3   CoreData                            0x00007fff8543a0af -[NSManagedObjectContext save:] + 207
4   BatteryNurse                        0x0000000100075ee6 __40-[CSTrackingEntry(Methods) deleteObject]_block_invoke_0 + 102
5   BatteryNurse                        0x000000010007514f __42-[CSCoreDataKernel(CoreData) executeSync:]_block_invoke_0 + 79
6   libSystem.B.dylib                   0x00007fff869bcfbb dispatch_barrier_sync_f + 79
7   BatteryNurse                        0x00000001000750ee -[CSCoreDataKernel(CoreData) executeSync:] + 110
8   BatteryNurse                        0x0000000100075e6f -[CSTrackingEntry(Methods) deleteObject] + 175
9   CoreFoundation                      0x00007fff817ff123 -[NSArray makeObjectsPerformSelector:] + 499
10  BatteryNurse                        0x000000010003a13f -[CSTracker(PrivateMethods) processAndSendBundlesToServer] + 383
11  BatteryNurse                        0x00000001000393a4 __23-[CSTracker flushAsync]_block_invoke_0 + 420
12  libSystem.B.dylib                   0x00007fff869c3d64 _dispatch_call_block_and_release + 15
13  libSystem.B.dylib                   0x00007fff869a28d2 _dispatch_queue_drain + 251
14  libSystem.B.dylib                   0x00007fff869a2734 _dispatch_queue_invoke + 57
15  libSystem.B.dylib                   0x00007fff869a22de _dispatch_worker_thread2 + 252
16  libSystem.B.dylib                   0x00007fff869a1c08 _pthread_wqthread + 353
17  libSystem.B.dylib                   0x00007fff869a1aa5 start_wqthread + 13

【参考方案1】：

您在保存对象时正在修改它。如果您正在观察NSManagedObjectContextObjectsDidChange（它将作为保存的一部分发布，但在实际保存发生之前），并且您更改对象是该通知的结果，您将创建一个循环：

当你调用-save:时CoreData首先调用-processPendingChanges:（如果有变化）。作为其中的一部分，CoreData 会发出 NSManagedObjectContextObjectsDidChange 通知。如果在处理通知时有其他对象发生更改，它会再次调用-processPendingChanges:，再次发送通知等。一旦没有待处理的更改，CoreData 会将对象持久保存到存储中。如果未决的更改不断出现，CoreData 最终将放弃并打印

The context is still dirty after 100 attempts.

这就是它的要点。