objective c - Understanding Instruments and Memory Management -


i'm in need of understanding how memory managed in objective c. know basics, if create , own it, must release yourself. however, when gets code such as: 

self.storedict = [nsmutabledictionary dictionarywithcontentsoffile:plistpath2];

do own this? must release memory?

self.storedict = [nsmutabledictionary dictionarywithcontentsoffile:plistpath2];  //73.3% leak    totalcharacters = [storedict count]; tagcounter = 1;  dictkeyarray = [[storedict allkeys] mutablecopy]; //13.3% leak

when instruments puts bunch of percentages next highlighted leaks, tell me? tell me size of leak relative total amount of memory leaked?
, 1 last thing.. normal amount of allocated memory continuously rise? or should stabilize somewhere? help! appreciated!

in cases, own objects returned methods names begin "alloc", "new", "copy", or "mutablecopy". of course, own send -retain. exceptions these rules should called out in documentation non-conforming methods.

see https://developer.apple.com/library/mac/documentation/cocoa/conceptual/memorymgmt/articles/mmrules.html#//apple_ref/doc/uid/20000994-sw1

instruments attributes leak line object created. however, that's not code leaked object. if pointer object passed other code , code did not balance retains , releases, code responsible leak. instruments can show history of retains , releases specific object, , you'll have review see code not discharging ownership responsibilities properly.

also, if object owned object , it's second object leaked, owned have leaked "transitively" were. so, higher-level objects have leaked before trying track down low-level objects have leaked. often, objects have leaked fewer instances root of graph of leaked objects.

whether normal memory keep rising or stabilize, depends little. usually, memory usage should stabilize. however, if app doing more , more, may normal memory usage keep increasing. example, if app receiving data on network , accumulating results so, memory usage rise more data arrives. if doesn't stop @ reasonable point, that's problem. on ios device, system kill it.


Comments

Post a Comment

Popular posts from this blog

java - Play! framework 2.0: How to display multiple image? -

i need display gallery of photos. here template: @(photos: list[photo]) @title = { <bold>gallery</bold> } @main(title,"photo"){ <ul class="thumbnails"> @for(photo <- photos) { <li class="span3"> <a href="#" class="thumbnail"> <img src="@photo.path" alt=""> </a> </li> } </ul> } and here controller method: public static result getphotos() { return ok(views.html.photo.gallery.render(photo.get())); } and here photo bean : @entity public class photo extends model { @id public long id; @required public string label; public string path; public photo(string path, string label) { this.path = path; this.label = label; } private static finder<long, photo> find = new finder<long, photo>( long.class, photo.class); public static list<phot...
Read more

gmail - Is there any documentation for read-only access to the Google Contacts API? -

i want read-only access user's google contacts. there stackoverflow member wanted this, , received following answer : yes, there is, use https://www.googleapis.com/auth/contacts.readonly scope , "view contacts". this exchange reference read-only access google contacts can find using google. simply using access token obtained attempt read usual google contacts api (i.e. https://www.google.com/m8/feeds ) fails insufficient permissions. similarly, using google contacts api on new target fails 404 errors (for example https://www.googleapis.com/auth/contacts.readonly/default/full ). is there documentation anywhere on how use api, or permissible way access google contacts api full read-write access?
Read more

php - Controller/JToolBar not working in Joomla 2.5 -

relevant code: jtoolbarhelper::custom('savecategories', 'save', '', 'save', false, false); ... <input type="hidden" name="controller" value="easyblogcontroller"> according can dig docs , own previous questions, should call savecategories() function in easyblogcontroller . i've tried setting value easyblog , easyblog.php (file name) current easyblogcontroller (class name). clicking on save button refreshes page. not redirect, echo or var_dump test code put in savecategories() function. var_dump ing jrequest::getvar('controller') , 'task' return correct values. creating controller object , using $controller->execute('task'); works. the values going depend on location of controller trying call, , have couple options here. typically there controller in base folder of component (likely components/com_easyblog) in file called controller.php , class name inside ...
Read more