Objective C NSArray Vs NSMutableArray performance

Question

With NSMutableArray we get additional methods like

addObject
insertObject
removeObjectAtIndex

Why we want to use non-mutable NSArray when we get additional methods in NSMutableArray? Is there any performance penalty when using NSMutableArray over NSArray?

Memory is quite a good reason. Block any attempts of modification is a good one too. — Larme
– Larme, Commented May 23, 2015 at 10:53
Why would you use a mutable array for things like storing the letters of the alphabet? Or something like that? — Fogmeister
– Fogmeister, Commented May 23, 2015 at 10:58

Community · Accepted Answer · 2017-05-23 12:03:59Z

0

Just check this link:

It is mentioned in the above link, just portraying in my words:

While calling an API that wants to copy the array and if you send -copy to an immutable array(NSArray), it just bumps the retain count, but while sending -copy to a mutable array(NSMutableArray) will allocate heap memory. So bumping the retain count is much faster than allocating heap memory.

Here comes the performance issue.

edited May 23, 2017 at 12:03

CommunityBot

11 silver badge

answered May 23, 2015 at 11:21

Vizllx

9,2261 gold badge43 silver badges79 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Objective C NSArray Vs NSMutableArray performance

1 Answer 1

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related