Replace a lot of blocks cause server lag

Hello.

I want to replace a lot of blocks (about 1000) it is not hard for world edit, but for my plugin it is.


First, in hashmap as key I keep blocks which I operate.
Seconds as HashMap loop (using iterator) I change these blocks to Material.AIR

Code:

        for(Iterator<Map.Entry <Block,ItemStack>> it = blocks.entrySet().iterator();it.hasNext();){
           Map.Entry <Block,ItemStack> entry = it.next();
e.getKey().setType(Material.AIR); 
}

And this cause the most lag (about 2 seconds)

 

How are you selecting those "1000" blocks and saving them?

 

@Kentakis

Don't save references to Blocks. Use BlockStates instead.

 

@mythbusterma
I change it to BlockState but now blockState.setType(Material.AIR) dont change blocks.

@edit
Ohh.. I forget to update block ... My fault.

Best Regards

///
I tested it, but it still cause lag. (for example scoreboard freeze for 2 seconds)

 

@Kentakis Are you sure it causes lag for the server or just your client? Either way, you can just span your block replacing out over several ticks.

 

@teej107 I'm replacing ~4,5k blocks

It cause lag for server because console of server is lagged too

 

@Kentakis

 

@teej107

U mean something like 'sleep' in this loop ?

 

@Kentakis No. That will make it lag even more. It involves using a scheduler.

 

@teej107

So I have to runTaskLater(20L) - and replace 50% blocks

And runTaskLater(30L) - to replace rest of blocks ?

 

@Kentakis not really.

 

@teej107
So what do you mean ?

 

1. @Kentakis
2. Create a repeating task
3. In the task, use a loop (I assume you are using one to replace blocks)
4. Check to see if X milliseconds have passed in the loop, if so, end the method early
5. Also in the loop, replace the blocks.
6. After the for loop, cancel the task.

 

I think that the best way to solve problem is to use NMS.

I try with:

Code:

  net.minecraft.server.v1_7_R4.World w = ((CraftWorld) world).getHandle();
  w.setTypeAndData(b.getX(),b.getY(),b.getZ(),net.minecraft.server.v1_7_R4.Block.getById(typeId),typeId,data);

2.

Code:

public void setBlockFast(Block b, int typeId, byte data) {
  net.minecraft.server.v1_7_R4.Chunk chunk = w.getChunkAt(b.getX() >> 4, b.getZ() >> 4);
  chunk.a( b.getX() & 0x0f, b.getY(), b.getZ() & 0x0f,net.minecraft.server.v1_7_R4.Block.getById(typeId), data);
   
  w.notify(b.getX(),b.getY(),b.getZ());
}

But it still lags main thread ... I try to use @teej107 idea, but this is too slow.


If I change blocks to AIR, there is NO LAG, but If I change blocks to "NOT AIR" IT CAUSE BIG LAG

I read something about light but I dont know how to use this knowledge

 

That's your client.

 

@Kentakis

Do what Teej said and spread out the changes over multiple ticks, this helps the server deal with the load.


@teej107

The server does do light calculations.

 

@teej107 For sure this is not Client side.

@mythbusterma Yes It is light calculations !

Please tell me how to 'turn it off'

 

@Kentakis

"Turning it off" is very difficult as it turns out.

There's some code to do it in dhutils (if that's still being maintained) that works pretty well.

EDIT: and you really shouldn't be working with the server internals (NMS) if you can't figure out how to spread the changes over multiple ticks.

 

@mythbusterma
I know how to do it in multiple ticks I exactly do it, but I said this is slow.

Hmm this function was taken from dhutils

Code:

public void setBlockFast(Block b, int typeId, byte data) {
  net.minecraft.server.v1_7_R4.Chunk chunk = w.getChunkAt(b.getX() >> 4, b.getZ() >> 4);
  chunk.a( b.getX() & 0x0f, b.getY(), b.getZ() & 0x0f,net.minecraft.server.v1_7_R4.Block.getById(typeId), data);
  
  w.notify(b.getX(),b.getY(),b.getZ());
}

But it update light too
//
Hmm I think, I know, this is 'a' function fault

 

@Kentakis

If you look in dhutils, there's a way to defer lighting calculations.

 

Dealing with that many blocks, I still think part of the "lag" is due to the client, but I'm not denying that there isn't any on the server. Don't mess with NMS and attempt what I suggested.

 

@teej107 @mythbusterma

In the runTaskTimer I change 'blockFast' 100 per 6 ticks.
Server is no laggy (I think) but now I dont know why, my minecraft LAG very well. (I mean that screen is freezed)


So how to load these blocks like 'worldedit' do it

 

@Kentakis Are you messing with NMS?

 

@teej107
Yes I do, I dont know how to load blocks without NMS and Light Calulations

 

@Kentakis

Just use Dhutils itself.

 

I use this, its something

Code:

public boolean QuickChangeBlockAt(final World world, final int x, final int y, final int z, final int blockId, final int data) {
        net.minecraft.server.v1_7_R4.World w = ((CraftWorld) world).getHandle();
        Chunk chunk = w.getChunkAt(x >> 4, z >> 4);
        return a(chunk, x & 0x0f, y, z & 0x0f, net.minecraft.server.v1_7_R4.Block.getById(blockId), data);
    }

    private boolean a(Chunk that, int i, int j, int k, net.minecraft.server.v1_7_R4.Block block, int l) {
        int i1 = k << 4 | i;

        if (j >= that.b[i1] - 1) {
            that.b[i1] = -999;
        }

        int j1 = that.heightMap[i1];
        net.minecraft.server.v1_7_R4.Block block1 = that.getType(i, j, k);
        int k1 = that.getData(i, j, k);

        if (block1 == block && k1 == l) {
            return false;
        } else {
            boolean flag = false;
            ChunkSection chunksection = that.getSections()[j >> 4];

            if (chunksection == null) {
                if (block == Blocks.AIR) { return false; }

                chunksection = that.getSections()[j >> 4] = new ChunkSection(j >> 4 << 4, !that.world.worldProvider.g);
                flag = j >= j1;
            }

            int l1 = that.locX * 16 + i;
            int i2 = that.locZ * 16 + k;

            if (!that.world.isStatic) {
                block1.f(that.world, l1, j, i2, k1);
            }

            // CraftBukkit start - Delay removing containers until after they're
            // cleaned up
            if (!(block1 instanceof IContainer)) {
                chunksection.setTypeId(i, j & 15, k, block);
            }
            // CraftBukkit end

            if (!that.world.isStatic) {
                block1.remove(that.world, l1, j, i2, block1, k1);
            } else if (block1 instanceof IContainer && block1 != block) {
                that.world.p(l1, j, i2);
            }

            // CraftBukkit start - Remove containers now after cleanup
            if (block1 instanceof IContainer) {
                chunksection.setTypeId(i, j & 15, k, block);
            }
            // CraftBukkit end

            if (chunksection.getTypeId(i, j & 15, k) != block) {
                return false;
            } else {
                chunksection.setData(i, j & 15, k, l);
                if (flag) {
                    that.initLighting();
                }
                TileEntity tileentity;

                if (block1 instanceof IContainer) {
                    tileentity = that.e(i, j, k);
                    if (tileentity != null) {
                        tileentity.u();
                    }
                }

                // CraftBukkit - Don't place while processing the
                // BlockPlaceEvent, unless it's a BlockContainer
                if (!that.world.isStatic && (!that.world.captureBlockStates || (block instanceof BlockContainer))) {
                    block.onPlace(that.world, l1, j, i2);
                }

                if (block instanceof IContainer) {
                    // CraftBukkit start - Don't create tile entity if placement
                    // failed
                    if (that.getType(i, j, k) != block) { return false; }
                    // CraftBukkit end

                    tileentity = that.e(i, j, k);
                    if (tileentity == null) {
                        tileentity = ((IContainer) block).a(that.world, l);
                        that.world.setTileEntity(l1, j, i2, tileentity);
                    }

                    if (tileentity != null) {
                        tileentity.u();
                    }
                }

                that.n = true;
                return true;
            }
        }
    }