3 level nested structs leading to out of memory

Question

Science Machine 2022-4-14

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1696125-3-level-nested-structs-leading-to-out-of-memory

编辑： Science Machine 2022-4-14

I'm initializing nested structs as:

struct('nestedLevelOne', repmat({struct('nestedLevelTwo',repmat({zeros(1,1080)}, [1,540]))} , [1,100]));

When I access and store data to these structures this is leading memory issues with 192gb ram on my workstation. Is there I am doing wrong with this?

2 个评论
显示无隐藏无

Akira Agata 2022-4-14

在 MATLAB Online 中打开

I could generate this nested structure without any issue.

Could you tell us more detail on the process when you faced the memory issue?

By the way, I would recommend break-down your code to be read easily, like:

c1 = repmat({zeros(1,1080)}, [1,540]);
c2 = repmat({struct('nestedLevelTwo',c1)} , [1,100]);
yourStruct = struct('nestedLevelOne', c2);

Science Machine 2022-4-14

编辑：Science Machine 2022-4-14

@Akira Agata when i start reading and writing to the structures with parfor loops, then this quickly leads to memory issue. So i was thinking that was due to

(1) how the structure was initialized (you just checked if the structure 'could' be initialized as such, which is not my issue),

(2) or maybe the fact i'm using nested structures (perhaps another data structure type would be better for lots of data?

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Chunru 2022-4-14

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1696125-3-level-nested-structs-leading-to-out-of-memory#answer_942440

在 MATLAB Online 中打开

It takes ~472MB memory as shown below.

a = struct('nestedLevelOne', ...
    repmat({struct('nestedLevelTwo',repmat({zeros(1,1080)}, [1,540]))} , [1,100]));
whos
  Name      Size                 Bytes  Class     Attributes

  a         1x100            472192864  struct              
a(1)
ans = struct with fields:
    nestedLevelOne: [1×540 struct]
a(1).nestedLevelOne(1)
ans = struct with fields:
    nestedLevelTwo: [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 … ]
size(a(1).nestedLevelOne(1).nestedLevelTwo)
ans = 1×2
           1        1080

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

Science Machine 2022-4-14

编辑：Science Machine 2022-4-14

@Chunru

I see, a structure i have is 47.69 gb, so I should save that piecemeal. Also, using parfor loops would create copies of this, which would explain why 20 workers crashed it

请先登录，再进行评论。