Chunk info UI explained

I can't say that this chunk info UI is intuitive, hope it is not a final design...
it was not very obvious for me from the first look what each its part means,
so I decided to make and share this picture:



my suggestions on improving it:
- show entity size
- show the total count of entities of this archetype
- allow to select one chunk and look at its content

 

Now that its explained it makes much more sense. Yea UI could use some work lol but good info tho

 

You forgot to explain, what 0 means.

 

0 means literally "nothing" in this case, it is a start value of the vertical axis - the minimum possible number of chunks
this vertical axis duplicated twice on the left and on the right of the chart

it'll never change - bars height always going to be from 0 to some integer number

same to 1
this is a start value of the horizontal axis (count of entities in the chunk)
it can't be less than 1 because empty chunks are deallocated.

 

Yep figured that one.

But generally I assume as well, the chart is just very basics mock-up, to polish it later.

 

The chart looks pretty amazing to me >_>

 

Oh, so thick line does not mean anything special? I have been trying to figure that out and thought it would expand thicker to the right..

 

as far as I understand there is no difference in bars thickness

here is how chunks graph may look after moving/removing some entities:
thick bars are simply few regular bars next to each other visually molded together



on this chart you see following:

Code (csharp):

1. (A,B) chunks: 8    chunk capacity:1336       entities per cunk: 664,661,659,641,701,633,682,337
2. (B) chunks: 6      chunk capacity:2004       entities per cunk: 2004,2004,2004,2004,2004,6
3. (A) chunks: 8      chunk capacity:1336       entities per cunk: 690,678,681,671,654,667,659,343

 

so whats the best method for utilizing chunks better? shouldnt the chunks always be filled to max as much as possible?

 

All this was explained on Unity LA month ago

 

Of course, chunks alway allocate 16K for self, and if you not use all this memory you will come across cache misses, and this breaks performance gains which DOD provide us.

 

What do you think about this case?



I have total 1092 chunks and 3275 entities. Chunks has split entities into:
entities per chunk: 3 (total of chunks 1091), 2 (total of chunks 1)

which is 3x1091 + 2x1 = 3275 entities

So i think that bar thickness can depend on entities count. It will be really good to have in Chunk info UI some kind of option to click on bar and get info about it.

 

oh missed that talk somehow

This is how the problem looks in chunk info view i think )
Your entities are too big - chunk can fit only 3 of them
Not sure what you doing, but right place for storing mesh data is shared component

 

I'm using IBufferElementData with fixed length of arrays. After that i split data from vertices/triangles to different entities. All this is because i need to iterate them multiple times to do my calculations.
Anyway shared component can only be use inside job as readonly so i can't modify it. Also i'm trying to avoid cache miss with this approach.
In my case was optimal size of dynamic buffer 128 so inside each chunk i have only 3 entities thats because i have
vertices 128 size
triangles 128*6 size
chuninfo - simple struct with info about chunk and part

All in all its about 1552byte (vertices), 3088byte (triangles), 8byte (chunkinfo) => 4648 bytes per entity.
16k / 4648 = 3 entities per chunk.

Even if you have all data inside shared componet you will have cache miss and if you have multiple unique shared components all entities will be split per unique shared component to chunk. So if i have 3 unique shared components i need 3 chunks which inside each will be only 1 entity.

 

hm... so you doing some huge procedural mesh generation...
I have no idea what is the right approach here.

 

Yeah something like that. Even still I don't know whats right or good. All I did was that i test and try measure my ideas.

For measurement I'm using https://docs.unity3d.com/Packages/com.unity.test-framework.performance@0.1/manual/index.html

 

have you tried to store each point and each triangle as a separate entity?

 

Yes, i try it. But problem was at creating so many entities. Too much overheat and iterating was only slightly better.

 

Can not use NativeArrays, with offset index?

 

I have got multiple "meshes" with vert/triang. Single NativeArray will be too long => cache miss.

 

Do you mind elaborate, why would you expect cache misses? Are you adding and removing vertices and polygons, other than just moving about?

 

In my case I'm trying to generate multiple terrain meshes with noise functions around player position. In editor you can set multiple layer of noise so I need as fast as it can be to iterate through vertices (only modify Y axis).

I have try it with single big NativeArray and it was about 30-40% slower then have multiple short entities of data. I know that creating NativeArray is faster then having multiple entities, but in my problem it is irrelevant. Because I can do this when scene is loading.
Anyway see video

how he explain of reading from RAM vs cache. So in my case I'm trying to reduce number of times reading from RAM. If I split data with IJobParallelFor and inside each Thread will be only single vertex I will waste cache. But if I have more data in single Thread which fit exactly 16k byte, you will get more speed up.
Only if I understand it right, maybe I'm wrong.

 

@xman7c7 Out of interest, have you used Burst by any chance?

 

In all my tests i used jobs with

Code (CSharp):

1. [BurstCompile]