High concurrency, multi-threaded, distributed did not know, what means you quit Ali, Tencent, Jingdong?

Java multi-threaded and highly concurrent actual practice

Let's look at some of the highly concurrent multi-threaded concurrency manufacturers face questions, see if you can know the result of a few!

CPU primitive level (1) synchronized is how to achieve?

(2) no lock, tend to lock, lock lightweight, heavyweight lock What's the difference, how to upgrade?

(3) threads between communication with the machine process between communications, cross-machine process between communications, have what method?

(4) the following three services, how to use the thread pool:

• High concurrency, short task execution time business
• Concurrency is not high, long task execution time business
• High concurrency, long-time business execution of business

(5) spike system, how to shore up the 100W level TPS (Taobao up to 540,000 TPS)?

If only the usual CRUD experience, do not understand the multi-threaded and highly concurrent, face to face such questions, the probability of a large loss.

Java high concurrency frequently asked interview questions

1. synchronized keyword bytecode primitive;
2. The volatile keyword bytecode primitive;
3. synchronized and volatile hardware level implementation;
4. No lock, tend to lock, lock lightweight, heavyweight upgrade process locks;
5. The basic concept of memory barrier;
6. How the JVM specification requirements memory barrier;
7. How to help java memory barrier hardware level to achieve high concurrency;
8. Interview Question 3 (inter-thread communication) of eight kinds of solution;

Java multi-threading line Internet frequently asked interview questions

1. Learning and thinking thread pool;
2. Good and bad use of the thread pool;
3. Why Ali manual recommends the development of a custom thread pool;
4. Custom thread pool of best practices;
5. Common thread pool types and application scenarios:

1）CachedPool

2）FixedThreadPool

3）ScheduledPool

4）WorkStealingPool

5）ForkJoinPool

1. More cattle than the threads in a thread X, the measurement results show the power of the pressure shred;

Java multi-threading

 

 

 

Java multi-threading skills

1. The concept and the advantages of multi-threaded processes and threads
2. The use of multi-threading
3. currentThread 0 method
4. isAlive 0 method
5. Methods sleep 0
6. getId0 method
7. Stop Thread
8. Pause thread
9. yie1d method
10. Thread priority
11. Daemon thread

Concurrent access to objects and variables

1. synchroni zed synchronization method
2. synchroni red sync block of statements
3. volatile keyword

Inter-thread communication

1. Waiting / notification mechanism
2. Use join the
3. Use of class ThreadLoca1
4. The class uses Inheri tabl eThreadLocea1

Lock of use

1. Use Reentr antLock class
2. Use Reentr antReadWr iteLock class

Timer Timer

1. Use the timer Timer

Singleton and multithreading

1. Load Now / "starving mode."
2. Lazy loading / "lazy mode"
3. Built implemented using static class Singleton
4. Serialization and deserialization achieve singleton
5. Stati e implemented using code blocks Singleton
6. Enum enumeration data type using single-mode embodiment
7. Improve the use enum enumeration achieve Singleton

Supplements Supplement

1. State of the thread
2. Thread Group
3. The thread has orderliness
4. Simpl eDateP ormat non-thread-safe
5. Exception handling thread appears
6. Handling exceptions in the thread group
7. Delivery thread exception handling

Java combat high concurrency

Basis - structuring concurrent applications - activity, performance and testing - Advanced Topics

 

 

 

 

 

Due to copy too long, Xiao Bian here is not to explain to you, show you in the form of screenshots, to learn high concurrency, multi-threaded, distributed real friends who are interested can be private letter I replied , "architecture books " get a free, easy to organize another, feel this article help you, take the trouble to help forward out to see more friends

Basics

• Thread safety
• Shared objects
• Composite object
• Fundamental building blocks

Thread safety

1. What is the thread safety
2. Atomicity
3. Race Conditions
4. Example: initializing the delay of race conditions
5. Complex operation
6. Locking mechanism
7. Built-in lock
8. Reentrant
9. Use locks to protect state
10. Activity and Performance

Shared objects

1. Visibility
2. Failure Data
3. Non-atomic operation 64
4. Locking and Visibility
5. Volatile variables
6. Release and escape
7. Thread closed
8. Ad-hoc thread closed
9. Stack closed
10. ThreadLoca1 class
11. Invariance
12. Final field
13. Example: Using Volatile release type immutable
14. Security release
15. Incorrect release: the correct object is destroyed
16. Immutable objects and initialize security
17. Common mode security release
18. The fact immutable objects
19. Variable Object
20. Secure shared object

Composite object

1. Design thread-safe class
2. Collect synchronization requirements
3. State-dependent operation
4. State ownership
5. Examples closed
6. Java monitor mode
7. Example: Vehicle Tracking
8. Thread safety commission
9. Example: based on vehicle delegate tracker
10. Become an independent state in
11. When the commission fails
12. Published underlying state variable
13. Example: Release Status vehicle tracker
14. To add functionality to an existing thread-safe classes
15. Client locking mechanism
16. combination
17. The synchronization strategy documented

Fundamental building blocks

1. Synchronization containers
2. Synchronization issues container class
3. Iterators and Concurr ent-Modi ficatExcepti on
4. Hide iterator
5. Concurrent containers
6. Concurr entHashMap
7. Additional atomic operation Map
8. CopyOnYri tar ayList
9. Blocking queue and producer-consumer model
10. Example: Desktop Search
11. Serial thread closed
12. Deque adhesion work level
13. Blocking method and interrupt method
14. Synchronization tools
15. Lockout
16. Future anD ask
17. signal
18. Fences

Structured concurrent applications

• Task Execution
• Cancel and close
• Use the thread pool
• The graphical user interface application

Task Execution

 

Cancel and close

 

Use the thread pool

 

The graphical user interface application

 

Activity, performance and testing

• Avoid dangerous activity
• Performance and scalability
• Testing concurrent programs

Avoid dangerous activity

 

Performance and scalability

 

Testing concurrent programs

 

Advanced Topics

• Explicit lock
• Build custom synchronization tool
• Varying in synchronization with the atoms nonblocking
• Java Memory Model

Explicit lock

1. Lock与Keentr antLock
2. Polling time lock with lock
3. Interruptible lock acquisition operation
4. Non-locking block structure
5. Performance considerations
6. Fairness

Build custom synchronization tool

1. State-dependent management
2. Example: delivery failure precondition to the caller
3. Example: Sleep achieved by polling and
4. Simple obstruction
5. Conditions queue
6. Conditions queue
7. Conditions predicate
8. Wake up early
9. Loss of signal
10. Notice
11. Example: Latches
12. Security issues subclass
13. Packaging Condition queue
14. Entrance and exit protocol agreement
15. Explicit Condi ti on objects
16. Symchr oni zer analysis
17. Abstr actQueuedSyn.chr oni acids
18. Java. Util. Concurr ent synchronizer class AQS
19. Reentr antLock
20. Semsphor e and CountDownLatch
21. FutureTask
22. Reentr antKeadKri teLock

Varying in synchronization with the atoms nonblocking

1. Lock与Keentr antLock
2. Polling time lock with lock
3. Interruptible lock acquisition operation
4. Non-locking block structure
5. Performance considerations
6. Fairness
7. Selecting between synchu oni red and Reentr antLock
8. Read - write lock

Java Memory Model

1. What is the memory model, why you need it
2. Platform memory model
3. Reordering
4. Java Memory Model Introduction
5. With synchronous
6. release
7. Unsafe release
8. Safe release
9. Security initialization mode
10. Double-checked locking
11. Security during initialization

distributed

 

Due to copy too long, Xiao Bian here is not to explain to you, show you in the form of screenshots, to learn high concurrency, multi-threaded, distributed real friends who are interested can be private letter I replied, "architecture books "get a free, easy to organize another, feel this article help you, take the trouble to help forward out to see more friends