memory-management

问题 Suppose we have created a Python module in C _xxx that contains an extension object xxx , and we do following: import _xxx class derived(_xxx.xxx): # ... d = derived() How does Python allocate memory for d behind the scenes? Eli Bendersky's article Python object creation sequence is the closest I've found, but it doesn't appear to cover this scenario. NOTE: there is already an answer HERE: I'm going to ask the author if he will consider migrating his answer here, as it is a good answer to a

问题 Hello everyone and thanks in advance! I've had a bit of an interesting journey with this problem. Here I figured out how to create a file-backed big matrix using the bigmemory package. This 7062 row by 364520 column matrix is the constraint matrix in a linear programming problem I'm trying to solve using the Rsymphony package. The code is below and the constraint matrix is called mat : Rsymph <- Rsymphony_solve_LP(obj ,mat[1:nrow(mat),1:ncol(mat)] ,dir ,rhs ,types="B",max=F, write_lp=T)

问题 when I look at my application in a memory utility (like Memory Usage app), it shows my application using 33MB of memory. If while debugging my app, I go into DDMS and look at the heap, it's taking 4MB. So at this point, I'm wondering where the other 29MB is being chewed up by. Secondly, my concern is that I could wind up spending a huge amount of time trying to trim that 4MB to something much smaller like say 2-3MB, but that hardly seems like I'm putting a dent in the memory usage. So how do

问题 let's say if you have class doing something on some other thread. And has delegate of its own. @protocol XRequestDelegate; @interface XRequest : NSObject { id<XRequestDelegate> delegate; } @property (nonatomic, retain) id<XRequestDelegate> delegate; - (void) doSomething; @end @protocol XRequestDelegate <NSObject> - (void)request:(XRequest *)request didFinish:(id)object; - (void)request:(XRequest *)request didFailWithError:(NSError*)error; @end doSomething eventually calls either request

问题 This question already has answers here : POSIX shared memory and semaphores permissions set incorrectly by open calls (2 answers) Closed 2 years ago . I am creating my shared memory using the below, trying either to open or create and setting unrestricted permissions. void createMemory(const int numBytes) { permissions perm; perm.set_unrestricted(); segment.reset(new managed_shared_memory(open_or_create, memory_name, numBytes, 0, perm)); // Exception throw on this line mutex.reset(new named

问题 Hey guys, I'm reviewing some questions but I can't really figure it out, i looked through the text book but i'm not sure where i can find answer... I know it would be quite hard to do memory diagrams w/o pictures but please bear with me. interface Lovable public void love(); class Foo implements Lovable public void love(); // something public int val() // return something1 public class Love public static void main(String args []) Foo foo = new Foo() foo.love() foo.love() int bar = =foo.val()

问题 My IOS program is not ARC, code like this: in the .h file i define five variables: { UILabel *label1,*lable2; UIView *dwView; NSMutableArray *wordsArray; } the code in the .m file like this: - (void)viewDidLoad{ [super viewDidLoad]; // Do any additional setup after loading the view from its nib. viewArray=[[NSMutableArray alloc]init]; } -(void)QuestionA{ dwView=[[UIView alloc] initWithFrame:CGRectMake(20, 50, 975.0, 620)]; label1 = [[UILabel alloc]initWithFrame:CGRectMake(10.0, 160.0, 950.0,

问题 My IOS program is not ARC, code like this: in the .h file i define five variables: { UILabel *label1,*lable2; UIView *dwView; NSMutableArray *wordsArray; } the code in the .m file like this: - (void)viewDidLoad{ [super viewDidLoad]; // Do any additional setup after loading the view from its nib. viewArray=[[NSMutableArray alloc]init]; } -(void)QuestionA{ dwView=[[UIView alloc] initWithFrame:CGRectMake(20, 50, 975.0, 620)]; label1 = [[UILabel alloc]initWithFrame:CGRectMake(10.0, 160.0, 950.0,

问题 My IOS program is not ARC, code like this: in the .h file i define five variables: { UILabel *label1,*lable2; UIView *dwView; NSMutableArray *wordsArray; } the code in the .m file like this: - (void)viewDidLoad{ [super viewDidLoad]; // Do any additional setup after loading the view from its nib. viewArray=[[NSMutableArray alloc]init]; } -(void)QuestionA{ dwView=[[UIView alloc] initWithFrame:CGRectMake(20, 50, 975.0, 620)]; label1 = [[UILabel alloc]initWithFrame:CGRectMake(10.0, 160.0, 950.0,

问题 Finished implementing the minimal Heap structure with awesome help from Micheal . Right now I have one thing missing so it dynamically grows. As you can see in this image, it isn't dynamic: Instead of having a fixed size when I do pmm_map_physical_virtual(0x800000,0xC0800000) , the max I can go to is 8MB which is from 0xC00000000-0xC0800000 ... but then I have to be aware not to overwrite the kernel, so I will technically have less than 8MB . Is there a way so that the heap just continues