iphone - Optimum memory management for NSMutableArrays -

a quick question need answered:

which uses more memory?

a nsmutablearray million objects or million nsmutablearrays 1 object?

will there difference?

a million nsmutablearrays 1 object consume more memory.

suppose basic nsmutablearray implementation has pointer , size elements:

• the pointer 4 8 bytes
• the size 4 8 bytes
• then each instance require 2 allocations (one object, 1 array), means addresses tracked someplace.
• add pointer isa, 4 8 bytes

now not how nsmutablearray implemented, gives idea of memory cost each instance in general purpose implementation.

so rather take sum of parts and:

• add 1000000 * sizeof(int*)
• or multiply 1000000?

that should give idea 1m arrays consume more memory. of course, can test using instruments if need real numbers.