This queue data structure is not strictly lock-free by what I consider the most reasonable definition. That definition is something like: A structure is lock-free if only if any thread can be indefinitely suspended at any point while still leaving the structure usable by the remaining threads. Of course this implies a suitable definition of … Read more
This message appears if a continuation you created via withCheckedContinuation, or withCheckedThrowingContinuation doesn’t report success or failure before being discarded. This is will lead to resource leaking: Resuming from a continuation more than once is undefined behavior. Never resuming leaves the task in a suspended state indefinitely, and leaks any associated resources. CheckedContinuation logs a … Read more
I recommend An Introduction to Parallel Programming by Pacheco. It’s clearly written, and a good intro to parallel programming. If you don’t care about something being tied to a language, then Java Concurrency in Practice is a great resource. Oracle’s online tutorial is free, but probably a bit more succinct than what you’re looking for. … Read more
The atomic “thing” in shared_ptr is not the shared pointer itself, but the control block it points to. meaning that as long as you don’t mutate the shared_ptr across multiple threads, you are ok. do note that copying a shared_ptr only mutates the control block, and not the shared_ptr itself. std::shared_ptr<int> ptr = std::make_shared<int>(4); for … Read more
It is useful to understand how node and V8 interact. Node handles waiting for I/O or timers from the operating system. When node wakes up from I/O or a timer, it generally has some JavaScript callbacks to invoke. When node runs these callbacks, control is passed into V8 until V8 returns back to node. So, … Read more
When your main() function ends, your program ends as well. It does not wait for other goroutines to finish. Quoting from the Go Language Specification: Program Execution: Program execution begins by initializing the main package and then invoking the function main. When that function invocation returns, the program exits. It does not wait for other … Read more
Yes, you can access a gzip file randomly by reading the entire thing sequentially once and building an index. See examples/zran.c in the zlib distribution. If you are in control of creating the gzip file, then you can optimize the file for this purpose by building in random access entry points and construct the index … Read more
In Dart 3, you should use a Record of Futures instead of a List/Iterable so that you can have heterogeneous types. Dart 3 provides wait extensions for such Records that are similar to Future.wait. (See sudormrfbin’s answer for an example.) If you must use Future.wait, you need to adapt each of your Future<T>s to a … Read more
Note that one interesting aspect of using struct{} for the type pushed to a channel (as opposed to int or bool), is that the size of an empty struct is… 0! See the recent article “The empty struct” (March 2014) by Dave Cheney. You can create as many struct{} as you want (struct{}{}) to push … Read more
This is what I think is happening (keep in mind I’m not familiar with HotSpot): 0xf36c9fd0: mov 0x6c(%ecx),%ebp ; vfoo 0xf36c9fd3: test %ebp,%ebp ; vfoo is null? 0xf36c9fd5: je 0xf36c9ff7 ; throw NullPointerException (I guess) 0xf36c9fd7: movl $0x1,0x8(%ebp) ; vfoo.x = 1 0xf36c9fde: mov 0x68(%ecx),%ebp ; sz 0xf36c9fe1: inc %ebx ; i++ 0xf36c9fe2: test %edi,0xf7725000 … Read more