Since $.getJSON() uses ajax configurations, just set the global ajax configs: // Set the global configs to synchronous $.ajaxSetup({ async: false }); // Your $.getJSON() request is now synchronous… // Set the global configs back to asynchronous $.ajaxSetup({ async: true });
Does this imply that, ‘there is no case where using a non-lock-free atomic type would be a better choice over using a lock-free atomic type when the latter is available’ ? (Mainly in terms of performance rather than ease-of-use). No. And that is, in general, not true. Suppose you have two cores and three threads … Read more
You asked for a tool or application answer, but what you really need is a a process answer. The underlying theme here is that you should be versioning your database DDL (and DML, when needed) and providing change scripts to be able to update any version of your database to a higher version. This set … Read more
No it’s not safe even though you may not sometimes observe any troubles. IIRC, the fmt package tries to be on the safe side, so probably intermixing of some sort may occur but no process crash, hopefully. This is an instance of a more universal Go documentation rule: Things are not safe for concurrent access … Read more
At first glance I thought I recognized this answer as the same algorithm that Alexander Terekhov introduced. But after studying it I believe that it is flawed. It is possible for two writers to simultaneously wait on m_exclusive_cond. When one of those writers wakes and obtains the exclusive lock, it will set exclusive_waiting_blocked = false … Read more
Please see my updates at the end of the answer, the situation has dramatically changed since Visual Studio 2015. The original answer is below. I made a very simple test and according to my measurements the std::mutex is around 50-70x slower than CRITICAL_SECTION. std::mutex: 18140574us CRITICAL_SECTION: 296874us Edit: After some more tests it turned out … Read more
Use the following in C++: #include <mutex> std::mutex _mutex; void f() { std::unique_lock<std::mutex> lock(_mutex); // access your resource here. }
Quartz 1 If you change your class to implement StatefulJob instead of Job, Quartz will take care of this for you. From the StatefulJob javadoc: stateful jobs are not allowed to execute concurrently, which means new triggers that occur before the completion of the execute(xx) method will be delayed. StatefulJob extends Job and does not … Read more
It is both complicated and differs from Unix to Unix variant. In Linux, for example, a system called Futex (Short for Fast Userspace Mutex) is used. In this system an atomic increment and test operation is performed on the mutex variable in user space. If the result of the operation indicates that there was no … Read more
Where I work we have developed an “offline” version of our main (web) application for users to be able to work on their laptops in locations where they do not have internet access. When the user comes back to the main site they need to synchronise the data they entered offline with our main application. … Read more