memory-management

问题 This question already has answers here : Java Thread Garbage collected or not (4 answers) Closed 5 years ago . From the Java API doc: The Java Virtual Machine continues to execute threads until following occurs: All threads that are not daemon threads have died, either by returning from the call to the run method or by throwing an exception that propagates beyond the run method. I hope my assumption is correct that once thread finishes its run() method it becomes eligible for garbage

问题 I'm trying to implement a simple memory manager to experiment with memory pooling mechanism and track memory leaks. I'm using VS2019 and so far my code only runs in release x86 mode. Changing the build configuration to debug or setting target platform to x64, results in an access violation error. Specifically, in debug mode the following line which calculates the available pool size, throws an exception "Unhandled exception thrown: read access violation. p was nullptr." return p->end - p-

问题 I'm writing a memory manager for my kernel (32 bit x86) In the course of this... I'm facing a bit of a dilemma.... Description of virtual memory map: Identity map of first 4 Mb Virtual address 0xC0000000 mapped to physical address 0x100000 (Also a 4 Mb map) My page directory is at physical address 0x9c000. My page table 1 is at physical address 0x9d000. My page table 2 is at physical addres 0x9e000. (I need only two page tables here :) ... These correspond to the identity map and higher

问题 I'm writing a memory manager for my kernel (32 bit x86) In the course of this... I'm facing a bit of a dilemma.... Description of virtual memory map: Identity map of first 4 Mb Virtual address 0xC0000000 mapped to physical address 0x100000 (Also a 4 Mb map) My page directory is at physical address 0x9c000. My page table 1 is at physical address 0x9d000. My page table 2 is at physical addres 0x9e000. (I need only two page tables here :) ... These correspond to the identity map and higher

问题 I have asked a similar question: Can a lower level cache have higher associativity and still hold inclusion? Suppose we have 2-level of cache. (L1 being nearest to CPU (inner / lower-level) and L2 being outside that, nearest to main memory) can L1 cache be write back? My attempt) I think we must have only write through cache and we cannot have write back cache in L1. If a block is replaced in the L1 cache then it has to be written back to L2 and also to main memory in order to hold inclusion.

问题 Looking through the C++ vector documents, pop_back() is a function that will not cause a reallocation of the vector's data. However, this only works for removing one member of the vector. I am trying to find a way to erase multiple members from the end of a vector. Originally I thought I would call pop_back() in a small for loop but I was wandering if there was a more convenient function that would do this for me? Edit: The Cplusplus vector erase() reference is not as clear as it should be as

问题 As Apple said in "The Swift Programming Language", it seems we should prefer unowned than weak whenever possible: If the captured reference will never become nil, it should always be captured as an unowned reference, rather than a weak reference. From the "Weak and Unowned References" section on this page I did know the difference between these two. But I am curious about is there any good reason for preferring unowned than weak ? I think the weak is much safer and we can just always write

问题 As Apple said in "The Swift Programming Language", it seems we should prefer unowned than weak whenever possible: If the captured reference will never become nil, it should always be captured as an unowned reference, rather than a weak reference. From the "Weak and Unowned References" section on this page I did know the difference between these two. But I am curious about is there any good reason for preferring unowned than weak ? I think the weak is much safer and we can just always write

问题 I've started programming erlang recently and there are a few things I want to understand regarding GC. As far as I understand there is a generational GC for the private heap of each process and a reference counting GC for the global shared heap. What I would like to know is if there is anyway to get: How many number of collection cycles? How many bytes are allocated and deallocated, on a global level or process level? What are the private heaps, and shared heap sizes? And can we define this

问题 I've started programming erlang recently and there are a few things I want to understand regarding GC. As far as I understand there is a generational GC for the private heap of each process and a reference counting GC for the global shared heap. What I would like to know is if there is anyway to get: How many number of collection cycles? How many bytes are allocated and deallocated, on a global level or process level? What are the private heaps, and shared heap sizes? And can we define this