realm-swift: mutex lock failed: Invalid argument while releasing Realm

It’s the same issue as #6686.

I already updated to 10.1.4 but still got these error reports every day. The difference is that it’s now crashing after I inserted new data into the table. It crashed after I deleted data when I was using Realm 5.4.4.

Actual Results

Fatal Exception: std::__1::system_error
mutex lock failed: Invalid argument
Fatal Exception: std::__1::system_error

com.google.firebase.crashlytics.ios.exception
0x0000000000000000
Crashed: com.google.firebase.crashlytics.ios.exception
0  pitt                           0x102656924 FIRCLSProcessRecordAllThreads + 392 (FIRCLSProcess.c:392)
1  pitt                           0x102656d08 FIRCLSProcessRecordAllThreads + 423 (FIRCLSProcess.c:423)
2  pitt                           0x10264d680 FIRCLSHandler + 34 (FIRCLSHandler.m:34)
3  pitt                           0x102649390 __FIRCLSExceptionRecord_block_invoke + 218 (FIRCLSException.mm:218)
4  libdispatch.dylib              0x1a30c3524 _dispatch_client_callout + 16
5  libdispatch.dylib              0x1a30a71fc _dispatch_lane_barrier_sync_invoke_and_complete + 56
6  pitt                           0x102648b28 FIRCLSExceptionRecord + 225 (FIRCLSException.mm:225)
7  pitt                           0x1026487c8 FIRCLSTerminateHandler() + 285 (FIRCLSException.mm:285)
8  libc++abi.dylib                0x1a31c614c std::__terminate(void (*)()) + 16
9  libc++abi.dylib                0x1a31c60e4 std::terminate() + 44
10 Realm                          0x1049f2190 __clang_call_terminate + 10
11 Realm                          0x104d999f0 realm::Group::detach() + 118
12 Realm                          0x104da36c4 realm::Transaction::close() + 60
13 Realm                          0x104da6350 TransactionDeleter(realm::Transaction*) + 20
14 Realm                          0x104dab360 std::__1::__shared_ptr_pointer<realm::Transaction*, void (*)(realm::Transaction*), std::__1::allocator<realm::Transaction> >::__on_zero_shared() + 20
15 Realm                          0x1049f4da0 std::__1::shared_ptr<realm::app::App>::~shared_ptr() + 64
16 Realm                          0x104b56980 realm::Realm::~Realm() + 96
17 Realm                          0x1049f4da0 std::__1::shared_ptr<realm::app::App>::~shared_ptr() + 64
18 libobjc.A.dylib                0x1a311ec90 object_cxxDestructFromClass(objc_object*, objc_class*) + 112
19 libobjc.A.dylib                0x1a3132cc4 objc_destructInstance + 88
20 libobjc.A.dylib                0x1a313973c _objc_rootDealloc + 52
21 Realm                          0x104b358b0 -[RLMRealm dealloc] + 92
22 libobjc.A.dylib                0x1a313c04c AutoreleasePoolPage::releaseUntil(objc_object**) + 180
23 libobjc.A.dylib                0x1a313bf44 objc_autoreleasePoolPop + 224
24 libswiftObjectiveC.dylib       0x1da16fbd8 autoreleasepool<A>(invoking:) + 68
25 pitt                           0x1024af36c closure #1 in PageCacheService.insert(caches:) + 4379505516 (<compiler-generated>:4379505516)
26 pitt                           0x1024cf51c thunk for @escaping @callee_guaranteed () -> () + 4379637020 (<compiler-generated>:4379637020)
27 libdispatch.dylib              0x1a30c29a8 _dispatch_call_block_and_release + 24
28 libdispatch.dylib              0x1a30c3524 _dispatch_client_callout + 16
29 libdispatch.dylib              0x1a30a0b3c _dispatch_lane_serial_drain$VARIANT$armv81 + 564
30 libdispatch.dylib              0x1a30a154c _dispatch_lane_invoke$VARIANT$armv81 + 396
31 libdispatch.dylib              0x1a30aa84c _dispatch_workloop_worker_thread + 580
32 libsystem_pthread.dylib        0x1a3114b74 _pthread_wqthread + 272
33 libsystem_pthread.dylib        0x1a3117740 start_wqthread + 8

Here’s another report which is similar to this issue. But there’s no any method from my codes in the callstack.

Fatal Exception: std::__1::system_error
mutex lock failed: Invalid argument
Fatal Exception: std::__1::system_error

com.google.firebase.crashlytics.ios.exception
0x0000000000000000
Crashed: com.google.firebase.crashlytics.ios.exception
0  pitt                           0x105302924 FIRCLSProcessRecordAllThreads + 392 (FIRCLSProcess.c:392)
1  pitt                           0x105302d08 FIRCLSProcessRecordAllThreads + 423 (FIRCLSProcess.c:423)
2  pitt                           0x1052f9680 FIRCLSHandler + 34 (FIRCLSHandler.m:34)
3  pitt                           0x1052f5390 __FIRCLSExceptionRecord_block_invoke + 218 (FIRCLSException.mm:218)
4  libdispatch.dylib              0x1b201d5ac _dispatch_client_callout + 20
5  libdispatch.dylib              0x1b202a360 _dispatch_lane_barrier_sync_invoke_and_complete + 60
6  pitt                           0x1052f4b28 FIRCLSExceptionRecord + 225 (FIRCLSException.mm:225)
7  pitt                           0x1052f47c8 FIRCLSTerminateHandler() + 285 (FIRCLSException.mm:285)
8  libc++abi.dylib                0x1b213540c std::__terminate(void (*)()) + 20
9  libc++abi.dylib                0x1b2135398 std::terminate() + 44
10 Realm                          0x1076aa190 __clang_call_terminate + 10
11 Realm                          0x107a519f0 realm::Group::detach() + 118
12 Realm                          0x107a5b6c4 realm::Transaction::close() + 60
13 Realm                          0x107a5e350 TransactionDeleter(realm::Transaction*) + 20
14 Realm                          0x107a63360 std::__1::__shared_ptr_pointer<realm::Transaction*, void (*)(realm::Transaction*), std::__1::allocator<realm::Transaction> >::__on_zero_shared() + 20
15 Realm                          0x1076acda0 std::__1::shared_ptr<realm::app::App>::~shared_ptr() + 64
16 Realm                          0x10780e980 realm::Realm::~Realm() + 96
17 Realm                          0x1076acda0 std::__1::shared_ptr<realm::app::App>::~shared_ptr() + 64
18 libobjc.A.dylib                0x1b208fd38 object_cxxDestructFromClass(objc_object*, objc_class*) + 116
19 libobjc.A.dylib                0x1b20a4020 objc_destructInstance + 92
20 libobjc.A.dylib                0x1b20aa8e8 _objc_rootDealloc + 60
21 Realm                          0x1077ed8b0 -[RLMRealm dealloc] + 92
22 libobjc.A.dylib                0x1b20ad380 AutoreleasePoolPage::releaseUntil(objc_object**) + 184
23 libobjc.A.dylib                0x1b20ad26c objc_autoreleasePoolPop + 232
24 libdispatch.dylib              0x1b201d588 _dispatch_last_resort_autorelease_pool_pop + 44
25 libdispatch.dylib              0x1b20244f0 _dispatch_lane_invoke + 488
26 libdispatch.dylib              0x1b202da5c _dispatch_workloop_worker_thread + 584
27 libsystem_pthread.dylib        0x1b2083718 _pthread_wqthread + 276
28 libsystem_pthread.dylib        0x1b20899c8 start_wqthread + 8

Steps for others to Reproduce

Use autoreleasepool in DispatchQueue.

Code Sample

    public func insert(caches c: [String:[MemoryCache]]?){
        guard let caches = c, !caches.isEmpty else {
            logHelper.i("Memory cache is empty.")
            return
        }

        autoreleasepool{ [weak self] in
            do {
                RealmCacheHelper.shared.invalidateSemaphore.wait()

                let logHelper = LogHelper(subsystem: "PageCacheService", category: "insertCache")

                var backgroundTaskID: UIBackgroundTaskIdentifier?

                // Request the task assertion and save the ID.
                backgroundTaskID = UIApplication.shared.beginBackgroundTask (withName: "PageCache insertion task.") {
                    logHelper.w("Background task expired.")
                    // End the task if time expires.
                    UIApplication.shared.endBackgroundTask(backgroundTaskID!)
                    backgroundTaskID = .invalid
                }

                defer{
                    RealmCacheHelper.shared.invalidateSemaphore.signal()
                    logHelper.i("Background task finished.")
                    UIApplication.shared.endBackgroundTask(backgroundTaskID!)
                    backgroundTaskID = .invalid
                }

                var memoryCaches: [MemoryCache] = caches.flatMap{ $0.value }

                logHelper.i("Making memory caches persisted \(memoryCaches.count).")

                let _realm = try RealmCacheHelper.shared.realm()

                _realm.beginWrite()

                for memoryCache in memoryCaches {
                    guard let mid = self?.getWorkerThreadMID(_realm) else {
                        return
                    }

                    let cache = MatrixCache.newInstance(
                            id: mid,
                            controllerId: memoryCache.controllerId,
                            page: memoryCache.page)

                    cache.content = memoryCache.matrixJson
                    cache.font = memoryCache.fontJson

                    _realm.add(cache)
                }

                try _realm.commitWrite()

                logHelper.i("All caches are persisted.")
            }
            catch {
                let logHelper = LogHelper(subsystem: "PageCacheService", category: "insertMatrixCache")
                logHelper.e("Failed to save page cache, error = %@", error: error)
                return
            }
        }

    }

class RealmCacheHelper {
    func realm() throws -> Realm {
        return try Realm(configuration: config)
    }
}

Version of Realm and Tooling

Realm framework version: 10.1.4

Realm Object Server version: N/A

Xcode version: 12.2

iOS/OSX version: 10, 12, 13, 14

Dependency manager + version: CocoaPods 1.10.0

About this issue

Original URL
State: closed
Created 4 years ago
Comments: 19 (5 by maintainers)

Most upvoted comments

Since the behaviour mentioned here (doing background work during the termination phase of an application) is not something we generally advise, I’m going to close this issue.

jsflax on Aug 4, 2021

@KimiChiu I had the same issue on my side, which occurred 100% in background state. After disabling file protection for realm directory the crash disappeared.

        // Disable file protection for realm directory to prevent crashes like mutex:locked
        // Source: https://github.com/realm/realm-cocoa/issues/7112#issuecomment-778218878
        let folderPath = configuration.fileURL!.deletingLastPathComponent().path
        do {
            let attributes = try FileManager.default.attributesOfItem(atPath: folderPath)
            let protectionType = attributes[.protectionKey] as? FileProtectionType
            if protectionType != .some(FileProtectionType.none) {
                try FileManager.default.setAttributes([.protectionKey: FileProtectionType.none], ofItemAtPath: folderPath)
            }
        } catch {
            print("Unable to set protection attributes for realm folder: \(error)")
        }

       return configuration
}

grighakobian on May 3, 2021

I don’t use any in memory realm database. The memoryCache in the code snippet is just a simple dictionary.

KimiChiu on Dec 14, 2020