CoreData strikes back - Speaker Deck

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CoreData наносит ответный удар с вертушки

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CoreData • The Core Data framework provides generalized and automated solutions to common tasks associated with object life-cycle and object graph management, including persistence. • Не база данных

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CoreData performance

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Откуда ждать проблем? • Игнорироание рекомендаций Apple • Многопоточность • Неоптимизированные запросы • CoreData cache misses • Неожиданные выборки • Неожиданное поведение

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Импорт данных

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Есть JSON @{ /*Person*/ @"id": @123456789, @"name": @"Johny Ive", @"email": @"[email protected]", @"phones": @[ @{ @"id": @12345, @"number": @"+3801234567", @"timestamp": @"12-11-2014" }, ] };

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@{ /*Person*/ @"id": @123456789, @"name": @"Johny Ive", @"email": @"[email protected]", @"phones": @[ @{ @"id": @12345, @"number": @"+3801234567", @"timestamp": @"12-11-2014" }, ] }; Есть JSON

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@{ /*Person*/ @"id": @123456789, @"name": @"Johny Ive", @"email": @"[email protected]", @"phones": @[ @{ @"id": @12345, @"number": @"+3801234567", @"timestamp": @"12-11-2014" }, ] }; Есть JSON @{ /*Person*/ @"id": @123456789, @"name": @"Johny Ive", @"email": @"[email protected]", @"phones": @[ @{ @"id": @12345, @"number": @"+3801234567", @"timestamp": @"12-11-2014" }, ] }; @{ /*Person*/ @"id": @123456789, @"name": @"Johny Ive", @"email": @"[email protected]", @"phones": @[ @{ @"id": @12345, @"number": @"+3801234567", @"timestamp": @"12-11-2014" }, ] }; @{ /*Person*/ @"id": @123456789, @"name": @"Johny Ive", @"email": @"[email protected]", @"phones": @[ @{ @"id": @12345, @"number": @"+3801234567", @"timestamp": @"12-11-2014" }, ] }; … @{ /*Person*/ @"id": @123456789, @"name": @"Johny Ive", @"email": @"[email protected]", @"phones": @[ @{ @"id": @12345, @"number": @"+3801234567", @"timestamp": @"12-11-2014" }, ] }; @{ /*Person*/ @"id": @123456789, @"name": @"Johny Ive", @"email": @"[email protected]", @"phones": @[ @{ @"id": @12345, @"number": @"+3801234567", @"timestamp": @"12-11-2014" }, ] }; @{ /*Person*/ @"id": @123456789, @"name": @"Johny Ive", @"email": @"[email protected]", @"phones": @[ @{ @"id": @12345, @"number": @"+3801234567", @"timestamp": @"12-11-2014" }, ] }; @{ /*Person*/ @"id": @123456789, @"name": @"Johny Ive", @"email": @"[email protected]", @"phones": @[ @{ @"id": @12345, @"number": @"+3801234567", @"timestamp": @"12-11-2014" }, ] };

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Есть MagicalRecord • https://github.com/magicalpanda/MagicalRecord/ • 4523 start • 666 commits • 52 contributors • 782 forks

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Есть MagicalRecord • https://github.com/magicalpanda/MagicalRecord/ • 4523 start • 666 commits • 52 contributors • 782 forks

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Также имеется в наличии • Xcode 5.1.1 • iPhone 5s • Схема Release • 20 итераций для каждого теста • Time Proﬁler

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Модель Person ————————— int64 personID (PK, no index); NSString *name; NSString *email; ————————— Phones Phone ————————— int64 phoneID (PK, no index) NSString *ddi; NSString *ddd; NSString *number; NSString *timestamp; 1 *

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Время импорта Insert Update t, sec 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 4.375 4.861

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– Time Proﬁle “Ну и тормозит”

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Код импорта (псевдо) + (id)importObject:(NSDictionary *)JSON { id object = [self goToDatabaseAndFindObjectForPrimaryKey:JSON[@"primaryKey"]]; if (object == nil) { object = [self createObject]; } [object importAttributes:JSON]; [object importRelationships:JSON]; return object; } ! + (void)importObjects:(NSArray *)objects { for (id object in objects) { [self importObject:object]; } }

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Time proﬁler #1

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Time proﬁler #2

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Improvement #1 • Проиндексируем Primary keys

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Improvement #1 • Проиндексируем Primary keys

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Время импорта PK Indexed Insert Update t, sec 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 4.375 4.294

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Код импорта даты NSDate * dateFromString(NSString *value, NSString *format) { NSDateFormatter *formatter = [[NSDateFormatter alloc] init]; [formatter setTimeZone:[NSTimeZone localTimeZone]]; [formatter setLocale:[NSLocale currentLocale]]; [formatter setDateFormat:format]; NSDate *parsedDate = [formatter dateFromString:value]; return parsedDate; }

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подправим..

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подправим.. следующий код: Потоконебезопасный Не освобождает память Это только для примера ! пожалуйста, не используйте его

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подправим.. NSDate * dateFromString(NSString *value, NSString *format) { static NSMutableDictionary *map = nil; static dispatch_once_t token; dispatch_once(&token, ^{ map = [NSMutableDictionary new]; }); NSDateFormatter *formatter = [map objectForKey:format]; if (!formatter) { formatter = [[NSDateFormatter alloc] init]; [formatter setTimeZone:[NSTimeZone localTimeZone]]; [formatter setLocale:[NSLocale currentLocale]]; [formatter setDateFormat:format]; [map setObject:formatter forKey:format]; } NSDate *parsedDate = [formatter dateFromString:value]; return parsedDate; }

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Время импорта PK Index, NSDateFormatter cache Insert Update t, sec 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 3.356 3.254

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Взгляд со стороны CoreData Instruments

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CoreData Instruments #1 Fetches CPU Usage

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CoreData Instruments #1 Fetches CPU Usage

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Есть MagicalRecord fork • https://github.com/seepel/MagicalRecord Fetches CPU Usage fork

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Есть MagicalRecord fork • https://github.com/seepel/MagicalRecord Fetches CPU Usage fork Fetches CPU Usage original

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Время импорта PK Index, NSDateFormatter cache, batch fetch Insert Update t, sec 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 1.337 1.236

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Когда уже будет что-то интересное..

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Insert Person *object = // find or create [object setPersonID:JSON[@"personIdentifier"]]; // . . . ! [object.managedObjectContext save:&error];

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Insert // Find sql: SELECT 0, t0.Z_PK, t0.Z_OPT, t0.ZEMAIL, t0.ZGENDER, t0.ZNAME, t0.ZPERSONID, t0.ZTIMESTAMP FROM ZPERSON t0 WHERE t0.ZPERSONID IN (?) ! // Save sql: INSERT INTO ZPERSON(Z_PK, Z_ENT, Z_OPT, ZEMAIL, ZGENDER, ZNAME, ZPERSONID, ZTIMESTAMP) VALUES(?, ?, ?, ?, ?, ?, ?, ?) Person *object = // find or create [object setPersonID:JSON[@"personIdentifier"]]; // . . . ! [object.managedObjectContext save:&error];

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Update // Find sql: SELECT 0, t0.Z_PK, t0.Z_OPT, t0.ZEMAIL, t0.ZGENDER, t0.ZNAME, t0.ZPERSONID, t0.ZTIMESTAMP FROM ZPERSON t0 WHERE t0.ZPERSONID IN (?) ! // Save sql: UPDATE ZPERSON SET Z_OPT = ? WHERE Z_PK = ? AND Z_OPT = ? Person *object = // find [object setPersonID:equalPersonID]; // . . . ! [object.managedObjectContext save:&error];

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Проверка на равенство - (void)MR_setValueIfDifferent:(id)value forKey:(NSString *)key { id currentValue = [self valueForKey:key]; if(currentValue == nil && value == nil) { return; } if((currentValue == nil && value != nil) || (currentValue != nil && value == nil)) { [self setValue:value forKey:key]; return; } if(![currentValue isEqual:value]) { [self setValue:value forKey:key]; } }

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Update // Find sql: SELECT 0, t0.Z_PK, t0.Z_OPT, t0.ZEMAIL, t0.ZGENDER, t0.ZNAME, t0.ZPERSONID, t0.ZTIMESTAMP FROM ZPERSON t0 WHERE t0.ZPERSONID IN (?) ! // Save Person *object = // fetch from database [object setPersonID:equalPersonID]; // . . . ! [object.managedObjectContext save:&error]; incl. equality check

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Время импорта PK Index, NSDateFormatter cache, batch fetch, equality check Insert Update t, sec 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 1.339 0.756

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Что у нас есть Fetches CPU Usage MagicalRecord fork

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Что у нас есть Fetches CPU Usage MagicalRecord fork

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Почему бы не сделать так? Fetches CPU Usage

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Как работает MR fork: @[ @{ @"id": @123456, /* ... */ @"phones": @[ @{@"id": @123, /* ... */ }, @{@"id": @1234, /* ... */ }, @{@"id": @12345, /* ... */ }, ], }, @{ @"id": @1300156, /* ... */ @"phones": @[ @{@"id": @5664523, /* ... */ }, @{@"id": @777412, /* ... */ }, @{@"id": @33345, /* ... */ }, ], }, /* ... */ ];

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Как можно ускорить @[ @{ @"id": @123456, /* ... */ @"phones": @[ @{@"id": @123, /* ... */ }, @{@"id": @1234, /* ... */ }, @{@"id": @12345, /* ... */ }, ], }, @{ @"id": @1300156, /* ... */ @"phones": @[ @{@"id": @5664523, /* ... */ }, @{@"id": @777412, /* ... */ }, @{@"id": @33345, /* ... */ }, ], }, /* ... */ ];

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Время импорта PK Index, NSDateFormatter cache, improved batch fetch, equality check Insert Update t, sec 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 0.173 0.081

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FastMappingKit • https://github.com/Yalantis/FastEasyMapping • pod "FastEasyMapping", :git => "https://github.com/Yalantis/FastEasyMapping.git"

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FastMappingKit • https://github.com/Yalantis/FastEasyMapping • pod "FastEasyMapping", :git => "https://github.com/Yalantis/FastEasyMapping.git" + (EMKManagedObjectMapping *)personWithPhonesMapping { return [EMKManagedObjectMapping mappingForEntityName:@"Person" configuration:^(EMKManagedObjectMapping *mapping) { [mapping setPrimaryKey:@"personID"]; [mapping addAttributeMappingDictionary:@{@"personID": @"id"}]; [mapping addAttributeMappingFromArray:@[@"name", @"email"]]; [mapping addAttributeMapping:[EMKAttributeMapping mappingOfProperty:@"timestamp" keyPath:@"timestamp" dateFormat:@"dd-MM-yyyy"]]; ! [mapping addToManyRelationshipMapping:[self phoneMapping] forProperty:@"phones" keyPath:@"phones"]; }]; }

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Неожиданные запросы

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CoreData faults NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:@"Phone"]; NSArray *phones = [context executeFetchRequest:request error:NULL]; ! for (Phone *phone in phones) { phone.person; } Faults Fetches

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CoreData faults NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:@"Phone"]; NSArray *phones = [context executeFetchRequest:request error:NULL]; [request setRelationshipKeyPathsForPrefetching:@[@"person"]]; ! for (Phone *phone in phones) { phone.person; } Faults Fetches

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Время No prefetch Prefetch t, ms 0.000 1.000 2.000 3.000 4.000 5.000 6.000 5.831 0.352

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sql NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:@"Phone"]; ! sql: SELECT 0, t0.Z_PK, t0.Z_OPT, t0.ZDDD, t0.ZDDI, t0.ZNUMBER, t0.ZPHONEID, t0.ZTIMESTAMP, t0.ZPERSON FROM ZPHONE t0 NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:@"Phone"]; [request setRelationshipKeyPathsForPrefetching:@[@"person"]]; ! sql: SELECT 0, t0.Z_PK, t0.Z_OPT, t0.ZDDD, t0.ZDDI, t0.ZNUMBER, t0.ZPHONEID, t0.ZTIMESTAMP, t0.ZPERSON FROM ZPHONE t0 . . . sql: SELECT 0, t0.Z_PK, t0.Z_OPT, t0.ZEMAIL, t0.ZGENDER, t0.ZNAME, t0.ZPERSONID, t0.ZTIMESTAMP FROM ZPERSON t0 WHERE t0.Z_PK IN (SELECT * FROM _Z_intarray0)

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CoreData stack и производительность

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CoreData stacks Persistent Store Coordinator Root Context ! (Private queue concurrency type) Main Context! (Main queue concurrency type) Background Context ! (Private queue concurrency type) stack #1

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CoreData stacks Persistent Store Coordinator Root Context ! (Private queue concurrency type) Main Context! (Main queue concurrency type) Background Context ! (Private queue concurrency type) stack #1 Persistent Store Coordinator Main Context ! (Main queue concurrency type) Background Context ! (Private queue concurrency type) stack #2

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Time Proﬁler Main thread Background thread stack #1 Main thread Background thread stack #2

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Time Proﬁler

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Тут надо что-то умное сказать

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Ссылки • Подопытные: • MagicalRecord • MagicalRecord fork • FastEasyMapping ! • Почитать: • CoreData performance • CD Stack performance shootout • Backstage with nested managed object contexts

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Спасибо