Parallel Training Methods

Author
Affiliation
Published

November 5, 2024

👀 Overview

📑 Outline

  1. Scaling: Overview
  2. Data Parallel Training
    1. Communication
    2. Why Distributed Training?
  3. Beyond Data Parallelism
    1. Additional Parallelism Strategies
  4. Large Language Models
  5. Hands On

🚀 Scaling: Overview

🐢 Training on a Single Device

flowchart LR
    subgraph G0["`GPU0`"]
        subgraph N0["`Network`"]
        end
        L0("`Loss`")
    end
    subgraph D["`Data`"]
        x("`x₀`")
        x1("`x₁`")
        x2("`x₂`")
    end
    x --> N0
    N0 --> L0
    L0 --> N0
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classDef green fill:#98E6A5,stroke:#333,stroke-width:1px,color:#000
classDef blue fill:#7DCAFF,stroke:#333,stroke-width:1px,color:#000
classDef purple fill:#FFCBE6,stroke:#333,stroke-width:1px,color:#000
classDef text fill:#CCCCCC02,stroke:#838383,stroke-width:0px,color:#838383
class x,L0 red
class x1, green
class x2, blue
class x3, grey
class N0,D,G0,n0 block

Figure 1: SLOW !! model size limited by GPU memory

🏎️ Training on Multiple GPUs: Data Parallelism

flowchart LR
    subgraph D["`Data`"]
        direction TB
        x("`x₀`")
        x1("`x₁`")
        x2("`x₂`")
    end
    direction LR
    subgraph G0["`GPU0`"]
        direction LR
        subgraph N0["`NN`"]
        end
        %%y0("`y₀`")
        L0["`Loss`"]
    end
    subgraph G1["`GPU1`"]
        direction LR
        subgraph N1["`NN`"]
        end
        L1["`Loss`"]
    end
    subgraph G2["`GPU2`"]
        direction LR
        subgraph N2["`NN`"]
        end
        L2["`Loss`"]
    end
    x --> G0
    x1 --> G1
    x2 --> G2
    N0 --> L0
    N1 --> L1
    N2 --> L2
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classDef yellow fill:#FFFF7F,stroke:#333,stroke-width:1px,color:#000
classDef green fill:#98E6A5,stroke:#333,stroke-width:1px,color:#000
classDef blue fill:#7DCAFF,stroke:#333,stroke-width:1px,color:#000
classDef purple fill:#FFCBE6,stroke:#333,stroke-width:1px,color:#000
class x,y0,L0 red
class x1,L1 green
class x2,L2 blue
class x3,ar grey
class D,N0,N1,N2,G0,G1,G2,GU block
class AR block
class bc text

Figure 2: Each GPU receives unique data at each step

Data Parallel: Forward Pass

flowchart LR
    subgraph D["`Data`"]
        direction TB
        %%xp("`xₙ₊₁`")
        x("`x₀`")
        x1("`x₁`")
        x2("`x₂`")
    end
    direction LR
    subgraph G0["`GPU0`"]
        direction LR
        subgraph N0["`NN`"]
        end
        %%y0("`y₀`")
        L0["`Loss`"]
    end
    subgraph G1["`GPU1`"]
        direction LR
        subgraph N1["`NN`"]
        end
        L1["`Loss`"]
    end
    subgraph G2["`GPU2`"]
        direction LR
        subgraph N2["`NN`"]
        end
        L2["`Loss`"]
    end
    subgraph AR["`Average Grads`"]
        direction TB
        ar("`(1/n) ∑ gₙ`")
    end
    x --> G0
    x1 --> G1
    x2 --> G2
    N0 --> L0
    N1 --> L1
    N2 --> L2
    G0 -.-> AR
    G1 -.-> AR
    G2 -.-> AR
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classDef text fill:#CCCCCC02,stroke:#838383,stroke-width:0px,color:#838383
class x,y0,L0 red
class x1,L1 green
class x2,L2 blue
class x3,ar grey
class D,N0,N1,N2,G0,G1,G2,GU block
class AR block
class bc text

Figure 3: Average gradients across all GPUs

Data Parallel: Backward Pass

flowchart RL
    subgraph D["`Data`"]
        direction TB
        x("`x₀`")
        x1("`x₁`")
        x2("`x₂`")
    end
    subgraph G0["`GPU0`"]
        direction RL
        subgraph N0["`NN`"]
        end
        L0["`Loss`"]
    end
    subgraph G1["`GPU1`"]
        direction RL
        subgraph N1["`NN`"]
        end
        L1["`Loss`"]
    end
    subgraph G2["`GPU2`"]
        direction RL
        subgraph N2["`NN`"]
        end
        L2["`Loss`"]
    end
    subgraph BC["`Send Updates`"]
        direction TB
    end
    BC -.-> G0
    BC -.-> G1
    BC -.-> G2
    L0 ~~~ N0
    L1 ~~~ N1
    L2 ~~~ N2
    G0 ~~~ x
    G1 ~~~ x1
    G2 ~~~ x2
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class x1,L1 green
class x2,L2 blue
class x3,ar grey
class D,N0,N1,N2,G0,G1,G2,GU block
class BC block
class bc text

Figure 4: Send global updates back to each GPU

Data Parallel: Full Setup

flowchart LR
    subgraph D["`Data`"]
        direction TB
        x("`x₀`")
        x1("`x₁`")
        x2("`x₂`")
    end
    direction LR
    subgraph G0["`GPU0`"]
        direction LR
        subgraph N0["`NN`"]
        end
        L0["`L0`"]
    end
    subgraph G1["`GPU1`"]
        direction LR
        subgraph N1["`NN`"]
        end
        L1["`L1`"]
    end
    subgraph G2["`GPU2`"]
        direction LR
        subgraph N2["`NN`"]
        end
        L2["`L2`"]
    end
    subgraph AR["`Average Grads`"]
        direction TB
        ar("`(1/n) ∑ gₙ`")
        bc("`Update Weights`")
        ar --> bc
    end
    x --> G0
    x1 --> G1
    x2 --> G2
    N0 --> L0
    N1 --> L1
    N2 --> L2
    G0 <-.-> AR
    G1 <-.-> AR
    G2 <-.-> AR
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classDef text fill:#CCCCCC02,stroke:#838383,stroke-width:0px,color:#838383
class x,y0,L0 red
class x1,L1 green
class x2,L2 blue
class x3,ar grey
class D,N0,N1,N2,G0,G1,G2,GU block
class AR block
class bc text

Figure 5: See: PyTorch / Distributed Data Parallel

Data Parallel: Training

flowchart TD
    subgraph D["`Data`"]
        direction LR
        x("`x₀`")
        x1("`x₁`")
        x2("`x₂`")
    end
    subgraph G0["`GPU0`"]
        direction TB
        subgraph N0["`NN`"]
        end
        L0["`L₀`"]
    end
    subgraph G1["`GPU1`"]
        direction TB
        subgraph N1["`NN`"]
        end
        L1["`L₁`"]
    end
    subgraph G2["`GPU2`"]
        direction TB
        subgraph N2["`NN`"]
        end
        L2["`L₂`"]
    end
    subgraph AR["`Average Grads`"]
        direction TB
        ar("`(1/n) ∑ gₙ`")
        bc("`Update Weights`")
        ar --> bc
    end
    x --> G0
    x1 --> G1
    x2 --> G2
    N0 --> L0
    N1 --> L1
    N2 --> L2
    G0 <-.-> AR
    G1 <-.-> AR
    G2 <-.-> AR
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classDef text fill:#CCCCCC02,stroke:#838383,stroke-width:0px,color:#838383
class x,y0,L0 red
class x1,L1 green
class x2,L2 blue
class x3,ar grey
class D,N0,N1,N2,G0,G1,G2,GU block
class AR block
class bc text

Figure 6

🗣️ Communication

AllReduce

Perform reductions on data (e.g. sum, min, max) across ranks, send result back to everyone.

flowchart TD
  subgraph R0["`Rank 0`"]
    x0("`x0`")
  end
  subgraph R1["`Rank 1`"]
    x1("`x1`")
  end
  subgraph R2["`Rank 2`"]
    x2("`x2`")
  end
  subgraph R3["`Rank 3`"]
    x3("`x3`")
  end
  subgraph AR["`Allreduce`"]
    xp["`x' = ∑ xₙ `"]
  end
  subgraph AR3["`Rank 3`"]
    xp3("`x'`")
  end
  subgraph AR2["`Rank 2`"]
    xp2("`x'`")
  end
  subgraph AR1["`Rank 1`"]
    xp1("`x'`")
  end
  subgraph AR0["`Rank 0`"]
    xp0("`x'`")
  end
  x0 --> AR
  x1 --> AR
  x2 --> AR
  x3 --> AR
  AR --> xp0
  AR --> xp1
  AR --> xp2
  AR --> xp3
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classDef blue fill:#7DCAFF,stroke:#333,stroke-width:1px,color:#000
classDef purple fill:#FFCBE6,stroke:#333,stroke-width:1px,color:#000
class R0,R1,R2,R3,AR,AR0,AR1,AR2,AR3 block
class xp,xp0,xp1,xp2,xp3, purple
class x0, red
class x1, green
class x2, blue
class x3, yellow

Figure 7: All-Reduce operation: each rank receives the reduction of input values across ranks.

Reduce

  • Perform a reduction on data across ranks, send to individual

flowchart TD
  subgraph R0["`Rank 0`"]
    x0("`x0`")
  end
  subgraph R1["`Rank 1`"]
    x1("`x1`")
  end
  subgraph R2["`Rank 2`"]
    x2("`x2`")
  end
  subgraph R3["`Rank 3`"]
    x3("`x3`")
  end
  subgraph AR["`Reduce`"]
    xp["`x'=reduce(x, 2, SUM)`"]
  end
  subgraph AR3["`Rank 3`"]
  end
  subgraph AR2["`Rank 2`"]
    xp2("`x'`")
  end
  subgraph AR1["`Rank 1`"]
  end
  subgraph AR0["`Rank 0`"]
  end
  x0 --> AR
  x1 --> AR
  x2 --> AR
  x3 --> AR
  AR --> AR3
  AR --> xp2
  AR --> AR1
  AR --> AR0
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classDef pink fill:#E599F7,stroke:#333,stroke-width:1px,color:#000
class R0,R1,R2,R3,AR,AR0,AR1,AR2,AR3, block
class xp,xp2 purple
class x0, red
class x1, green
class x2, blue
class x3, yellow

Figure 8: Reduce operation: one rank receives the reduction of input values across ranks

Broadcast

flowchart TD
  subgraph R3["`Rank 3`"]
  end
  subgraph R2["`Rank 2`"]
    x2("`x2`")
  end
  subgraph R1["`Rank 1`"]
  end
  subgraph R0["`Rank 0`"]
  end
  subgraph AR["` `"]
    xp["`broadcast(x2, 2)`"]
  end
  subgraph AR3["`Rank 3`"]
    xp3("`x2`")
  end
  subgraph AR2["`Rank 2`"]
    xp2("`x2`")
  end
  subgraph AR1["`Rank 1`"]
    xp1("`x2`")
  end
  subgraph AR0["`Rank 0`"]
    xp0("`x2`")
  end
  x2 --> AR
  AR --> AR3
  AR --> AR2
  AR --> AR1
  AR --> AR0
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classDef blue fill:#7DCAFF,stroke:#333,stroke-width:1px,color:#000
classDef yellow fill:#FFFF7F,stroke:#333,stroke-width:1px,color:#000
class R0,R1,R2,R3,AR0,AR1,AR2,AR3,AR, block
class x2,xp0,xp1,xp2,xp3 blue
class xp, text

Figure 9: broadcast (send) a tensor x from one rank to all ranks

AllGather

flowchart LR
  subgraph R0["`Rank 0`"]
    x0("`x0`")
  end
  subgraph R1["`Rank 1`"]
    x1("`x1`")
  end
  subgraph R2["`Rank 2`"]
    x2("`x2`")
  end
  subgraph R3["`Rank 3`"]
    x3("`x3`")
  end
  subgraph AG["`Allgather`"]
    %%xp0["`z=[empty_like(x) for _ in range(4)]`"]
    %%xp1["`dist.all_gather(z, x)`"]
  end
  subgraph AG3["`Rank 3`"]
    direction TB
    xp03("`x0`")
    xp13("`x1`")
    xp23("`x2`")
    xp33("`x3`")
  end
  subgraph AG2["`Rank 2`"]
    direction TB
    xp02("`x0`")
    xp12("`x1`")
    xp22("`x2`")
    xp32("`x3`")
  end
  subgraph AG1["`Rank 1`"]
    direction TB
    xp01("`x0`")
    xp11("`x1`")
    xp21("`x2`")
    xp31("`x3`")
  end
  subgraph AG0["`Rank 0`"]
    direction TB
    xp00("`x0`")
    xp10("`x1`")
    xp20("`x2`")
    xp30("`x3`")
  end
  x0 --> AG
  x1 --> AG
  x2 --> AG
  x3 --> AG
  AG --> AG0
  AG --> AG1
  AG --> AG2
  AG --> AG3
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class xp0,xp1, text
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class xp00,xp01,xp02,xp03, red
class xp10,xp11,xp12,xp13, green
class xp20,xp21,xp22,xp23, blue
class xp30,xp31,xp32,xp33, yellow
class x0, red
class x1, green
class x2, blue
class x3, yellow

Figure 10: Gathers tensors from the whole group in a list.

Scatter

flowchart TD
  subgraph R3["`Rank 3`"]
  end
  subgraph R2["`Rank 2`"]
  end
  subgraph R1["`Rank 1`"]
    direction TB
    xp0("`x0`")
    xp1("`x1`")
    xp2("`x2`")
    xp3("`x3`")
  end
  subgraph R0["`Rank 0`"]
  end
  subgraph S["`Scatter`"]
  end
  subgraph S3["`Rank 3`"]
    x3("`x3`")
  end
  subgraph S2["`Rank 2`"]
    x2("`x2`")
  end
  subgraph S1["`Rank 1`"]
    x1("`x1`")
  end
  subgraph S0["`Rank 0`"]
    x0("`x0`")
  end
  %%R0 --> S
  R1 --> S
  %%R2 --> S
  %%R3 --> S
  S --> S0
  S --> S1
  S --> S2
  S --> S3
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classDef purple fill:#FFCBE6,stroke:#333,stroke-width:1px,color:#000
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class AG0,AG1,AG2,AG3,S,R0,R1,R2,R3,S0,S1,S2,S3, block
class x0,xp0, red
class x1,xp1, green
class x2,xp2, blue
class x3,xp3, yellow

Figure 11: Scatters a list of tensors to the whole group

⚡ Why Distributed Training?

  • N workers each processing unique batch1 of data:
    • [micro_batch_size = 1] \times [N GPUs] \rightarrow [global_batch_size = N]
  • Improved gradient estimators
    • Smooth loss landscape
    • Less iterations needed for same number of epochs
      • common to scale learning rate lr *= sqrt(N)
  • See: Large Batch Training of Convolutional Networks

Why Distributed Training? Speedup!

Table 1: Recent progress
Year Author GPU Batch Size # GPU TIME (s) ACC
2016 He P100 256 8 104,400 75.30%
2019 Yamazaki V100 81,920 2048 72 75.08%

Dealing with Data

  • At each training step, we want to ensure that each worker receives unique data
  • This can be done in one of two ways:
    1. Manually partition data (ahead of time)
      • Assign unique subsets to each worker
      • Each worker can only see their local portion of the data
      • Most common approach
    2. From each worker, randomly select a mini-batch
      • Each worker can see the full dataset
      • ⚠️ When randomly selecting, it is important that each worker uses different seeds to ensure they receive unique data

Broadcast Initial State

  • At the start of training (or when loading from a checkpoint), we want all of our workers to be initialized consistently
    • Broadcast the model and optimizer states from rank() == 0 worker

flowchart TD
0["GPU0"] --> 1["GPU 1"]
CKPT --> 0
0 --> 2["GPU 2"]
0 --Model + Optim. State-->3["GPU 3"]
0 --> X["`...`"]
0 --> N["GPU N"]
classDef block fill:#CCCCCC02,stroke:#838383,stroke-width:1px,color:#838383
classDef text fill:#CCCCCC02,stroke:#838383,stroke-width:0px,color:#838383
class 0,1,2,3,N,X,CKPT block

Figure 12: To ensure all workers have the same copies, we load on RANK==0 and broadcast

Best Practices

⏰ Keeping things in Sync

Computation stalls during communication !!

Keeping the communication to computation ratio small is important for effective scaling.

  • Use parallel IO whenever possible
    • Feed each rank from different files
    • Use MPI IO to have each rank read its own batch from a file
    • Use several ranks to read data, MPI to scatter to remaining ranks
      • Most practical in big at-scale training
  • Take advantage of data storage
  • Use the right optimizations for Aurora, Polaris, etc.
  • Preload data when possible
    • Offloading to a GPU frees CPU cycles for loading the next batch of data
      • minimize IO latency this way

Going Beyond Data Parallelism

Going beyond Data Parallelism: DeepSpeed + ZeRO

  • Depending on the ZeRO stage (1, 2, 3), we can offload:
    1. Stage 1: optimizer states \left(P_{\mathrm{os}}\right)
    2. Stage 2: gradients + opt. states \left(P_{\mathrm{os}+\mathrm{g}}\right)
    3. Stage 3: model params + grads + opt. states \left(P_{\mathrm{os}+\mathrm{g}+\mathrm{p}}\right)
Figure 13: DeepSpeed + ZeRO

Fully Sharded Data Parallel: 🔥 PyTorch + FSDP

Figure 14: FSDP Workflow. Source

🕸️ Additional Parallelism Strategies

Pipeline Parallelism (PP)

flowchart TB
    subgraph G0["`GPU 0`"]
        direction LR
        a0("`Layer 0`")
        b0("`Layer 1`")
    end
    subgraph G1["`GPU 1`"]
        direction LR
        a1("`Layer 2`")
        b1("`Layer 3`")
    end
    a0 -.-> b0
    b0 --> a1
    a1 -.-> b1
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classDef purple fill:#FFCBE6,stroke:#333,stroke-width:1px,color:#000
class G0,G1, block
class a0, red
class b0, green
class a1, blue
class b1, yellow

Figure 15: Pipeline Parallelism

Tensor Parallel (TP)

  • Each tensor is split up into multiple chunks
  • Each shard of the tensor resides on its designated GPU
  • During processing each shard gets processed separately (and in parallel) on different GPUs
    • synced at the end of the step
  • See: 🤗 Model Parallelism for additional details

flowchart LR
   subgraph G0["`GPU0`"]
    direction TB
    a0("`Layer 0`")
    b0("`Layer 1`")
    c0("`Layer 2`")
    d0("`Layer 3`")
   end
   subgraph G1["`GPU1`"]
    direction TB
    a1("`Layer 0`")
    b1("`Layer 1`")
    c1("`Layer 2`")
    d1("`Layer 3`")
   end
   a0 <-.-> a1
   b0 <-.-> b1
   c0 <-.-> c1
   d0 <-.-> d1
classDef red fill:#ff8181,stroke:#333,stroke-width:1px,color:#000
classDef orange fill:#FFC47F,stroke:#333,stroke-width:1px,color:#000
classDef yellow fill:#FFFF7F,stroke:#333,stroke-width:1px,color:#000
classDef green fill:#98E6A5,stroke:#333,stroke-width:1px,color:#000
classDef blue fill:#7DCAFF,stroke:#333,stroke-width:1px,color:#000
classDef purple fill:#FFCBE6,stroke:#333,stroke-width:1px,color:#000
classDef block fill:#CCCCCC02,stroke:#838383,stroke-width:1px,color:#838383
class G0,G1, block
class a0,a1 red
class b0,b1 green
class c0,c1 blue
class d0,d1 yellow

Figure 16: Tensor Parallel Training

Tensor Parallel (TP)

  • Suitable when the model is too large to fit onto a single device (CPU / GPU)
  • Typically more complicated to implement than data parallel training
    • This is what one may call horizontal parallelism
    • Communication whenever dataflow between two subsets
  • argonne-lcf/Megatron-DeepSpeed
  • 🤗 huggingface/nanotron

flowchart LR
   subgraph G0["`GPU0`"]
    direction TB
    a0("`Layer 0`")
    b0("`Layer 1`")
    c0("`Layer 2`")
    d0("`Layer 3`")
   end
   subgraph G1["`GPU1`"]
    direction TB
    a1("`Layer 0`")
    b1("`Layer 1`")
    c1("`Layer 2`")
    d1("`Layer 3`")
   end
   a0 <-.-> a1
   b0 <-.-> b1
   c0 <-.-> c1
   d0 <-.-> d1
classDef red fill:#ff8181,stroke:#333,stroke-width:1px,color:#000
classDef orange fill:#FFC47F,stroke:#333,stroke-width:1px,color:#000
classDef yellow fill:#FFFF7F,stroke:#333,stroke-width:1px,color:#000
classDef green fill:#98E6A5,stroke:#333,stroke-width:1px,color:#000
classDef blue fill:#7DCAFF,stroke:#333,stroke-width:1px,color:#000
classDef purple fill:#FFCBE6,stroke:#333,stroke-width:1px,color:#000
classDef block fill:#CCCCCC02,stroke:#838383,stroke-width:1px,color:#838383
class G0,G1, block
class a0,a1 red
class b0,b1 green
class c0,c1 blue
class d0,d1 yellow

Figure 17: Tensor Parallel Training
  • Split up network over multiple workers
    • Each receives disjoint subset
    • All communication associated with subsets are distributed
  • Communication whenever dataflow between two subsets
  • Typically more complicated to implement than data parallel training
  • Suitable when the model is too large to fit onto a single device (CPU / GPU)
  • argonne-lcf/Megatron-DeepSpeed
  • 🤗 huggingface/nanotron

See: 🤗 Model Parallelism for additional details

Tensor (/ Model) Parallel Training: Example

Want to compute: y = \sum_{i} x_{i} W_{i} = x_0 W_0 + x_1 W_1 + x_2 W_2 where each GPU only has only its portion of the full weights as shown below

  1. Compute: x_{0} W_{0}\rightarrow GPU1
  2. Compute: x_{0} W_{0} + x_{1} W_{1}\rightarrow GPU2
  3. Compute: y = \sum_{i} x_{i} W_{i}

flowchart TD
  subgraph X2["`GPU2`"]
    direction LR
    c("`W₂`")
  end
  subgraph X1["`GPU1`"]
    direction TB
    b("`W₁`")
  end
  subgraph X0["`GPU0`"]
    a("`W₀`")
  end
  X0 <-.-> X1
  X1 <-.-> X2
  t0("`x₀`") --> X0
  t1("`x₁`") --> X1
  t2("`x₂`") --> X2
classDef redText fill:#CCCCCC02,stroke:#FF8181,stroke-width:2px,color:#838383,font-weight:500
classDef orangeText fill:#CCCCCC02,stroke:#FFC47F,stroke-width:2px,color:#838383
classDef yellowText fill:#CCCCCC02,stroke:#FFFF7F,stroke-width:2px,color:#838383
classDef blueText fill:#CCCCCC02,stroke:#7DCAff,stroke-width:2px,color:#838383
classDef greenText fill:#CCCCCC02,stroke:#98E6A5,stroke-width:2px,color:#838383
classDef red fill:#ff8181,stroke:#333,stroke-width:1px,color:#000
classDef orange fill:#FFC47F,stroke:#333,stroke-width:1px,color:#000
classDef yellow fill:#FFFF7F,stroke:#333,stroke-width:1px,color:#000
classDef green fill:#98E6A5,stroke:#333,stroke-width:1px,color:#000
classDef blue fill:#7DCAFF,stroke:#333,stroke-width:1px,color:#000
classDef purple fill:#FFCBE6,stroke:#333,stroke-width:1px,color:#000
classDef block fill:#CCCCCC02,stroke:#838383,stroke-width:1px,color:#838383
classDef text fill:#CCCCCC02,stroke:#838383,stroke-width:0px,color:#838383
class a, red
class b, green
class c, blue
class X0,X1,X2, block
%%class t0, redText
%%class t1, greenText
%%class t2, blueText
class a0,b0,c0, text

Tensor (Model) Parallelism2

  • In Tensor Paralleism each GPU processes only a slice of a tensor and only aggregates the full tensor for operations that require the whole thing.
    • The main building block of any transformer is a fully connected nn.Linear followed by a nonlinear activation GeLU.
      • Y = GeLU(XA), where X and Y are the input and output vectors, and A is the weight matrix.
    • If we look at the computation in matrix form, it’s easy to see how the matrix multiplication can be split between multiple GPUs:

Tensor Parallelism

Figure 18: Tensor Parallel GEMM. This information is based on (the much more in-depth) TP Overview by @anton-l

3D Parallelism

  • DP + TP + PP (3D) Parallelism

Deciding on a Parallelism Strategy

  • Model fits onto a single GPU:
    • Normal use
  • Model DOES NOT fit on a single GPU:
    • ZeRO + Offload CPU (or, optionally, NVMe)
  • Largest layer DOES NOT fit on a single GPU:
    • ZeRO + Enable Memory Centric Tiling (MCT)
      • MCT Allows running of arbitrarily large layers by automatically splitting them and executing them sequentially.
  • Model fits onto a single GPU
  • With sufficiently fast connectivity between nodes, these three strategies should be comparable.

    • Otherwise, PP > ZeRO \simeq TP.
  • When you have fast inter-node connectivity:

    • ZeRO (virtually NO modifications)
    • PP + ZeRO + TP + DP (less communication, at the cost of MAJOR modifications)
      • when you have slow inter-node connectivity and still low on GPU memory:

        DP + PP + TP + ZeRO-1
    • NOTE: TP is almost always used within a single node, e.g.
      TP <= GPUS_PER_NODE

🦙 Large Language Models

Figure 20: Large Language Models have (LLM)s have taken the NLP community world by storm3.

🔮 Emergent Abilities

Figure 21: See Wei et al. (2022), Yao et al. (2023)

🦜 Training LLMs

Figure 22: Visualization from Yang et al. (2023)
Figure 23: It’s hungry! Wei et al. (2022)

♻️ Life-Cycle of the LLM

  1. Data collection + preprocessing
  2. Pre-training
    • Architecture decisions, model size, etc.
  3. Supervised Fine-Tuning
    • Instruction Tuning
    • Alignment
  4. Deploy (+ monitor, re-evaluate, etc.)
Figure 24: Pre-training: Virtually all of the compute used during pre-training4.

🎀 Life-Cycle of the LLM

  1. Data collection + preprocessing
  2. Pre-training
    • Architecture decisions, model size, etc.
  3. Supervised Fine-Tuning
    • Instruction Tuning
    • Alignment
  4. Deploy (+ monitor, re-evaluate, etc.)
Figure 25: Fine-tuning: Fine-tuning actually updates the model’s weights to make the model better at a certain task5.

⏩ Forward Pass

Figure 26: Language Model trained for causal language modeling6.

💬 Generating Text

Figure 27: Language Model trained for causal language modeling7.

👋 Hands On

ai-science-training-series / 06_parallel_training

🧑‍💻 Hands On: Getting Started

  1. 🌱 Clone Repo(s):

  2. 🐍 Setup Python:

    export PBS_O_WORKDIR=$(pwd) && source deps/ezpz/src/ezpz/bin/utils.sh
    ezpz_setup_python
    ezpz_setup_job

📦 Install {ezpz, wordplay}

  1. Install Python packages:

    1. saforem2/ezpz:

      python3 -m pip install -e "./deps/ezpz" --require-virtualenv
    2. saforem2/wordplay:

      # from inside `wordplay/`
      python3 -m pip install -e . --require-virtualenv
  2. Test distributed setup:

    mpirun -n "${NGPUS}" python3 -m ezpz.test_dist

    See: 🍋 ezpz/test_dist.py

ezpz: Example [video]

Figure 28: Example: using 🍋 ezpz.test_dist to train a small model using DDP

Install wordplay 🎮💬

Figure 29: The simplest, fastest repository for training / finetuning GPT based models. Figure from karpathy/nanoGPT

Prepare Data

python3 wordplay/data/shakespeare_char/prepare.py
# Using HF_DATASETS_CACHE=/home/foremans/tmp/polaris-talk/2024-07-17-073327/wordplay/data/shakespeare_char/.cache/huggingface
# length of dataset in characters: 1,115,394
# all the unique characters:
#  !$&\',-.3:;?ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz
# vocab size: 65
# train has 1,003,854 tokens
# val has 111,540 tokens

Launch Training (DDP)

launch python3 -m wordplay \
    train.backend=DDP \
    train.eval_interval=100 \
    data=shakespeare \
    train.dtype=bf16 \
    model.batch_size=64 \
    model.block_size=1024 \
    train.max_iters=1000 \
    train.log_interval=10 \
    train.compile=false \
    | tee wordplay-gpt2-DDP.log

Training: Example Output

[2024-07-17 07:42:11.746540][INFO][__init__:156] - Setting logging level to 'INFO' on 'RANK == 0'
[2024-07-17 07:42:11.748763][INFO][__init__:157] - Setting logging level to 'CRITICAL' on all others 'RANK != 0'
[2024-07-17 07:42:11.749453][INFO][__init__:160] - To disable this behavior, and log from ALL ranks (not recommended), set: 'export LOG_FROM_ALL_RANKS=1'  in your environment, and re-run.
[2024-07-17 07:42:11.772718][INFO][configs:81] - Setting HF_DATASETS_CACHE to /home/foremans/tmp/polaris-talk/2024-07-17-073327/wordplay/.cache/huggingface/datasets
[2024-07-17 07:42:15.341532][INFO][dist:358] - [device='cuda'][rank=2/3][local_rank=2/3][node=0/0]
[2024-07-17 07:42:15.342381][INFO][dist:358] - [device='cuda'][rank=1/3][local_rank=1/3][node=0/0]
[2024-07-17 07:42:15.342430][INFO][dist:358] - [device='cuda'][rank=3/3][local_rank=3/3][node=0/0]
[2024-07-17 07:42:15.348657][INFO][dist:95] -

[dist_info]:
  • DEVICE=cuda
  • DEVICE_ID=cuda:0
  • DISTRIBUTED_BACKEND=nccl
  • GPUS_PER_NODE=4
  • HOSTS=['x3101c0s13b0n0.hsn.cm.polaris.alcf.anl.gov']
  • HOSTFILE=/var/spool/pbs/aux/2024084.polaris-pbs-01.hsn.cm.polaris.alcf.anl.gov
  • HOSTNAME=x3101c0s13b0n0.hsn.cm.polaris.alcf.anl.gov
  • LOCAL_RANK=0
  • MACHINE=Polaris
  • NUM_NODES=1
  • NGPUS=4
  • NGPUS_AVAILABLE=4
  • NODE_ID=0
  • RANK=0
  • SCHEDULER=PBS
  • WORLD_SIZE_TOTAL=4
  • WORLD_SIZE_IN_USE=4
  • LAUNCH_CMD=mpiexec --verbose --envall -n 4 -ppn 4 --hostfile /var/spool/pbs/aux/2024084.polaris-pbs-01.hsn.cm.polaris.alcf.anl.gov --cpu-bind depth -d 16

[2024-07-17 07:42:15.351446][INFO][dist:725] - [0/4] Using device='cuda' with backend='DDP' + 'nccl' for distributed training.
[2024-07-17 07:42:15.356169][INFO][dist:358] - [device='cuda'][rank=0/3][local_rank=0/3][node=0/0]
[2024-07-17 07:42:15.356692][WARNING][dist:364] - Using [4 / 4] available "cuda" devices !!
[2024-07-17 07:42:15.359571][INFO][configs:317] - Loading val from /home/foremans/tmp/polaris-talk/2024-07-17-073327/wordplay/data/shakespeare_char/val.bin
[2024-07-17 07:42:15.360138][INFO][configs:317] - Loading train from /home/foremans/tmp/polaris-talk/2024-07-17-073327/wordplay/data/shakespeare_char/train.bin
[2024-07-17 07:42:15.361154][INFO][configs:442] - Tokens per iteration: 262,144
[2024-07-17 07:42:15.361574][INFO][configs:465] - Using self.ptdtype=torch.float16 on self.device_type='cuda'
[2024-07-17 07:42:15.362002][INFO][configs:471] - Initializing a new model from scratch
[2024-07-17 07:42:15.362529][INFO][dist:874] - Setting up wandb from rank: 0
[2024-07-17 07:42:15.362896][INFO][dist:875] - Using: WB PROJECT: WordPlay
[2024-07-17 07:42:16.451786][INFO][dist:905] - W&B RUN: [still-frog-17](https://wandb.ai/aurora_gpt/WordPlay/runs/6by9vpcj)
[2024-07-17 07:42:16.464106][INFO][dist:312] - Updating wandb.run: still-frog-17 config with "DIST_INFO"
[2024-07-17 07:42:16.469424][INFO][dist:938] - Running on machine='Polaris'
[2024-07-17 07:42:16.471151][WARNING][__main__:89] - {
    "train": {
        "framework": "pytorch",
        "backend": "DDP",
        "device": null,
        "seed": null,
        "port": null,
        "ds_config_path": null,
        "precision": null,
        "ngpus": null,
        "use_wandb": true,
        "eval_interval": 100,
        "log_interval": 10,
        "eval_iters": 200,
        "eval_only": false,
        "always_save_checkpoint": false,
        "init_from": "scratch",
        "wandb_project": "WordPlay",
        "max_iters": 1000,
        "warmup_iters": 100,
        "dtype": "bf16",
        "compile": false
    },
    "model": {
        "n_layer": 12,
        "n_head": 12,
        "n_embd": 768,
        "batch_size": 64,
        "block_size": 1024,
        "activation": "gelu",
        "dropout": 0.0,
        "bias": false,
        "vocab_size": 65
    },
    "data": {
        "dataset": "shakespeare_char",
        "out_dir": "out-shakespeare-char",
        "root_path": null
    },
    "optimizer": {
        "gas": 1,
        "name": "AdamW",
        "learning_rate": 0.0006,
        "weight_decay": 0.1,
        "beta1": 0.9,
        "beta2": 0.95,
        "grad_clip": 1.0,
        "decay_lr": true,
        "lr_decay_iters": 600000,
        "min_lr": 6e-05
    }
}
[2024-07-17 07:42:16.474305][WARNING][__main__:90] - Output dir: /home/foremans/tmp/polaris-talk/outputs/runs/pytorch/DDP/2024-07-17/07-42-13
[2024-07-17 07:42:16.474922][INFO][trainer:246] - Initializing a new model from scratch
[2024-07-17 07:42:17.258904][INFO][model:255] - number of parameters: 85.00M
[2024-07-17 07:42:17.290004][INFO][trainer:264] - Model size: num_params=85003776
[2024-07-17 07:42:17.292626][INFO][model:445] - num decayed parameter tensors: 50, with 85,771,008 parameters
[2024-07-17 07:42:17.293296][INFO][model:449] - num non-decayed parameter tensors: 25, with 19,200 parameters
[2024-07-17 07:42:17.515324][CRITICAL][trainer:316] - "devid='cuda:1'"
[2024-07-17 07:42:17.515340][CRITICAL][trainer:316] - "devid='cuda:2'"
[2024-07-17 07:42:17.515465][CRITICAL][trainer:316] - "devid='cuda:3'"
[2024-07-17 07:42:18.431814][INFO][model:465] - using fused AdamW: True
[2024-07-17 07:42:18.432620][CRITICAL][trainer:316] - "devid='cuda:0'"
[2024-07-17 07:42:19.951020][INFO][trainer:356] - • self.model=GPT(
  (transformer): ModuleDict(
    (wte): Embedding(65, 768)
    (wpe): Embedding(1024, 768)
    (drop): Dropout(p=0.0, inplace=False)
    (h): ModuleList(
      (0-11): 12 x Block(
        (ln_1): LayerNorm()
        (attn): CausalSelfAttention(
          (c_attn): Linear(in_features=768, out_features=2304, bias=False)
          (c_proj): Linear(in_features=768, out_features=768, bias=False)
          (attn_dropout): Dropout(p=0.0, inplace=False)
          (resid_dropout): Dropout(p=0.0, inplace=False)
        )
        (ln_2): LayerNorm()
        (mlp): MLP(
          (c_fc): Linear(in_features=768, out_features=3072, bias=False)
          (act_fn): GELU(approximate='none')
          (c_proj): Linear(in_features=3072, out_features=768, bias=False)
          (dropout): Dropout(p=0.0, inplace=False)
        )
      )
    )
    (ln_f): LayerNorm()
  )
  (lm_head): Linear(in_features=768, out_features=65, bias=False)
)
[2024-07-17 07:42:19.955340][INFO][trainer:357] - • self.grad_scaler=<torch.cuda.amp.grad_scaler.GradScaler object at 0x145a38f0f090>
[2024-07-17 07:42:19.956897][INFO][trainer:358] - • self.model_engine=DistributedDataParallel(
  (module): GPT(
    (transformer): ModuleDict(
      (wte): Embedding(65, 768)
      (wpe): Embedding(1024, 768)
      (drop): Dropout(p=0.0, inplace=False)
      (h): ModuleList(
        (0-11): 12 x Block(
          (ln_1): LayerNorm()
          (attn): CausalSelfAttention(
            (c_attn): Linear(in_features=768, out_features=2304, bias=False)
            (c_proj): Linear(in_features=768, out_features=768, bias=False)
            (attn_dropout): Dropout(p=0.0, inplace=False)
            (resid_dropout): Dropout(p=0.0, inplace=False)
          )
          (ln_2): LayerNorm()
          (mlp): MLP(
            (c_fc): Linear(in_features=768, out_features=3072, bias=False)
            (act_fn): GELU(approximate='none')
            (c_proj): Linear(in_features=3072, out_features=768, bias=False)
            (dropout): Dropout(p=0.0, inplace=False)
          )
        )
      )
      (ln_f): LayerNorm()
    )
    (lm_head): Linear(in_features=768, out_features=65, bias=False)
  )
)
[2024-07-17 07:42:19.961066][INFO][trainer:359] - • self.optimizer=AdamW (
Parameter Group 0
    amsgrad: False
    betas: (0.9, 0.95)
    capturable: False
    differentiable: False
    eps: 1e-08
    foreach: None
    fused: True
    lr: 0.0006
    maximize: False
    weight_decay: 0.1

Parameter Group 1
    amsgrad: False
    betas: (0.9, 0.95)
    capturable: False
    differentiable: False
    eps: 1e-08
    foreach: None
    fused: True
    lr: 0.0006
    maximize: False
    weight_decay: 0.0
)
[2024-07-17 07:42:19.988827][INFO][trainer:802] - Startup time: 6.7125
                Training Legend
┏━━━━━━━━━━━━━┳━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
┃    abbr     ┃ desc                           ┃
┡━━━━━━━━━━━━━╇━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┩
│    step     │ Current training iteration     │
│    loss     │ Loss value                     │
│     dt      │ Elapsed time per training step │
│     dtf     │ Elapsed time per forward step  │
│     dtb     │ Elapsed time per backward step │
│     sps     │ Samples per second             │
│ sps_per_gpu │ Samples per second (per GPU)
│     tps     │ Tokens per second              │
│ tps_per_gpu │ Tokens per second (per GPU)
│     mfu     │ Model flops utilization        │
│ train_loss  │ Training loss value            │
│  val_loss   │ Validation loss value          │
└─────────────┴────────────────────────────────┘
[2024-07-17 07:42:21.451865][INFO][trainer:820] - ['prompt']: 'What is an LLM?'
[2024-07-17 07:42:21.452667][INFO][trainer:824] - ['response']:
What is an LLM?eelEl\'$nltPwBSWal,;PWw bbu\'HiyP\'FWwF &AhW:ygrn kk-\'\'KFlMwnlEfflkc,elpWaWtgml$Pgglhllw lglhFllzczPAFHpeAAPPSltgkrWPPhlEMgcrN ggPWt-WPSSzHSkkrzzk.FFrtSSkgMll&gFXr,hghaueaVPW-pHFF-gg,,,FF,,kbApgg gg\'aWWzzkk\'a\'CggHl$bGeA,FFk,,SF;UF,,aZ ;gglee$,k.US&kg:S,,zVzzc
[2024-07-17 07:43:01.573073][INFO][trainer:885] - step=10 loss=3.154310 dt=0.282833 dtf=0.005247 dtb=0.011417 sps=14.142633 sps_per_gpu=3.535658 tps=926851.609409 tps_per_gpu=231712.902352 mfu=46.288281 train_loss=4.125778 val_loss=4.128809
[2024-07-17 07:43:04.402750][INFO][trainer:885] - step=20 loss=2.660851 dt=0.306263 dtf=0.005233 dtb=0.011419 sps=13.060678 sps_per_gpu=3.265170 tps=855944.613638 tps_per_gpu=213986.153409 mfu=45.934162 train_loss=4.125778 val_loss=4.128809
[2024-07-17 07:43:07.237507][INFO][trainer:885] - step=30 loss=2.543283 dt=0.283021 dtf=0.005238 dtb=0.011245 sps=14.133211 sps_per_gpu=3.533303 tps=926234.088226 tps_per_gpu=231558.522057 mfu=45.966490 train_loss=4.125778 val_loss=4.128809
[2024-07-17 07:43:10.077248][INFO][trainer:885] - step=40 loss=2.503963 dt=0.285001 dtf=0.005213 dtb=0.011471 sps=14.035061 sps_per_gpu=3.508765 tps=919801.749941 tps_per_gpu=229950.437485 mfu=45.963461 train_loss=4.125778 val_loss=4.128809
[2024-07-17 07:43:12.917039][INFO][trainer:885] - step=50 loss=2.477469 dt=0.283532 dtf=0.005166 dtb=0.011294 sps=14.107763 sps_per_gpu=3.526941 tps=924566.380009 tps_per_gpu=231141.595002 mfu=45.984530 train_loss=4.125778 val_loss=4.128809
[2024-07-17 07:43:15.760749][INFO][trainer:885] - step=60 loss=2.471083 dt=0.284630 dtf=0.005140 dtb=0.011224 sps=14.053326 sps_per_gpu=3.513332 tps=920998.786204 tps_per_gpu=230249.696551 mfu=45.985675 train_loss=4.125778 val_loss=4.128809
[2024-07-17 07:43:18.602785][INFO][trainer:885] - step=70 loss=2.458894 dt=0.283926 dtf=0.005219 dtb=0.010383 sps=14.088155 sps_per_gpu=3.522039 tps=923281.352698 tps_per_gpu=230820.338174 mfu=45.998106 train_loss=4.125778 val_loss=4.128809
[2024-07-17 07:43:21.451433][INFO][trainer:885] - step=80 loss=2.489088 dt=0.285537 dtf=0.005183 dtb=0.011373 sps=14.008683 sps_per_gpu=3.502171 tps=918073.060430 tps_per_gpu=229518.265108 mfu=45.983282 train_loss=4.125778 val_loss=4.128809
[2024-07-17 07:43:24.302241][INFO][trainer:885] - step=90 loss=2.471990 dt=0.300767 dtf=0.005445 dtb=0.010290 sps=13.299337 sps_per_gpu=3.324834 tps=871585.359388 tps_per_gpu=217896.339847 mfu=45.737774 train_loss=4.125778 val_loss=4.128809
[2024-07-17 07:43:27.153275][INFO][trainer:885] - step=100 loss=2.445556 dt=0.285869 dtf=0.005182 dtb=0.011251 sps=13.992403 sps_per_gpu=3.498101 tps=917006.151328 tps_per_gpu=229251.537832 mfu=45.743655 train_loss=4.125778 val_loss=4.128809
[2024-07-17 07:43:28.182553][INFO][trainer:820] - ['prompt']: 'What is an LLM?'
[2024-07-17 07:43:28.183179][INFO][trainer:824] - ['response']:

What is an LLM?

Goupay my winghimithell bls ger t bon sinthard ht omind be,
And lereind h py balithand frd oforondof wimon me hageas thinero mand,
Thacanes,
An frift ghik med d herthecke ntore thack couthen ale, t thit ang d m t h chy me fache ag, wit my hathan glat ng
[2024-07-17 07:44:06.025837][INFO][trainer:760] - Saving checkpoint to: /home/foremans/tmp/polaris-talk/outputs/runs/pytorch/DDP/2024-07-17/07-42-13
[2024-07-17 07:44:06.026607][INFO][trainer:761] - Saving model to: /home/foremans/tmp/polaris-talk/outputs/runs/pytorch/DDP/2024-07-17/07-42-13/model.pth
[2024-07-17 07:44:07.682968][INFO][configs:141] - Appending /home/foremans/tmp/polaris-talk/outputs/runs/pytorch/DDP/2024-07-17/07-42-13 to /home/foremans/tmp/polaris-talk/2024-07-17-073327/wordplay/src/ckpts/checkpoints.log
[2024-07-17 07:44:10.519506][INFO][trainer:885] - step=110 loss=2.433923 dt=0.285038 dtf=0.005757 dtb=0.011762 sps=14.033209 sps_per_gpu=3.508302 tps=919680.367894 tps_per_gpu=229920.091974 mfu=45.762304 train_loss=2.439494 val_loss=2.478951
[2024-07-17 07:44:13.362148][INFO][trainer:885] - step=120 loss=2.429014 dt=0.284445 dtf=0.005222 dtb=0.011486 sps=14.062460 sps_per_gpu=3.515615 tps=921597.361532 tps_per_gpu=230399.340383 mfu=45.788661 train_loss=2.439494 val_loss=2.478951
[2024-07-17 07:44:16.210694][INFO][trainer:885] - step=130 loss=2.402059 dt=0.285559 dtf=0.005199 dtb=0.011765 sps=14.007633 sps_per_gpu=3.501908 tps=918004.211586 tps_per_gpu=229501.052897 mfu=45.794438 train_loss=2.439494 val_loss=2.478951
[2024-07-17 07:44:19.061546][INFO][trainer:885] - step=140 loss=2.374062 dt=0.285476 dtf=0.005239 dtb=0.011453 sps=14.011662 sps_per_gpu=3.502916 tps=918268.297093 tps_per_gpu=229567.074273 mfu=45.800956 train_loss=2.439494 val_loss=2.478951
[2024-07-17 07:44:21.917283][INFO][trainer:885] - step=150 loss=2.365385 dt=0.285846 dtf=0.005125 dtb=0.011320 sps=13.993568 sps_per_gpu=3.498392 tps=917082.475791 tps_per_gpu=229270.618948 mfu=45.800900 train_loss=2.439494 val_loss=2.478951
[2024-07-17 07:44:24.771924][INFO][trainer:885] - step=160 loss=2.317337 dt=0.280788 dtf=0.005173 dtb=0.011249 sps=14.245602 sps_per_gpu=3.561401 tps=933599.792506 tps_per_gpu=233399.948127 mfu=45.883340 train_loss=2.439494 val_loss=2.478951
[2024-07-17 07:44:27.626812][INFO][trainer:885] - step=170 loss=2.256231 dt=0.284973 dtf=0.005141 dtb=0.011299 sps=14.036416 sps_per_gpu=3.509104 tps=919890.544506 tps_per_gpu=229972.636126 mfu=45.889069 train_loss=2.439494 val_loss=2.478951
[2024-07-17 07:44:30.480952][INFO][trainer:885] - step=180 loss=2.216419 dt=0.286555 dtf=0.005180 dtb=0.011402 sps=13.958906 sps_per_gpu=3.489726 tps=914810.852170 tps_per_gpu=228702.713043 mfu=45.868857 train_loss=2.439494 val_loss=2.478951
[2024-07-17 07:44:33.337342][INFO][trainer:885] - step=190 loss=2.145123 dt=0.291456 dtf=0.005409 dtb=0.019347 sps=13.724205 sps_per_gpu=3.431051 tps=899429.467247 tps_per_gpu=224857.366812 mfu=45.773849 train_loss=2.439494 val_loss=2.478951
[2024-07-17 07:44:36.194584][INFO][trainer:885] - step=200 loss=2.068149 dt=0.285703 dtf=0.005153 dtb=0.011286 sps=14.000555 sps_per_gpu=3.500139 tps=917540.393411 tps_per_gpu=229385.098353 mfu=45.778791 train_loss=2.439494 val_loss=2.478951
[2024-07-17 07:44:37.224149][INFO][trainer:820] - ['prompt']: 'What is an LLM?'
[2024-07-17 07:44:37.224745][INFO][trainer:824] - ['response']:

What is an LLM?

LORTESS LA:
No, sighappat selace? don downd sourciceans note cancen up sof liond
This and my man, werame, of re thee
Thise not will I on land brond sul me a fingore?

FLER:
Tisint your not nare lame o igen,-to brorst.

SamERS:
Sin:
I\'l hell she lor hen w
[2024-07-17 07:45:14.409129][INFO][trainer:760] - Saving checkpoint to: /home/foremans/tmp/polaris-talk/outputs/runs/pytorch/DDP/2024-07-17/07-42-13
[2024-07-17 07:45:14.409820][INFO][trainer:761] - Saving model to: /home/foremans/tmp/polaris-talk/outputs/runs/pytorch/DDP/2024-07-17/07-42-13/model.pth
[2024-07-17 07:45:16.366935][INFO][configs:141] - Appending /home/foremans/tmp/polaris-talk/outputs/runs/pytorch/DDP/2024-07-17/07-42-13 to /home/foremans/tmp/polaris-talk/2024-07-17-073327/wordplay/src/ckpts/checkpoints.log
[2024-07-17 07:45:19.245061][INFO][trainer:885] - step=210 loss=1.982169 dt=0.283305 dtf=0.005223 dtb=0.011284 sps=14.119042 sps_per_gpu=3.529760 tps=925305.515083 tps_per_gpu=231326.378771 mfu=45.822019 train_loss=2.045786 val_loss=2.148510
[2024-07-17 07:45:22.092430][INFO][trainer:885] - step=220 loss=1.897731 dt=0.284759 dtf=0.005217 dtb=0.011187 sps=14.046945 sps_per_gpu=3.511736 tps=920580.608106 tps_per_gpu=230145.152026 mfu=45.837327 train_loss=2.045786 val_loss=2.148510
[2024-07-17 07:45:24.942639][INFO][trainer:885] - step=230 loss=1.817213 dt=0.285266 dtf=0.005208 dtb=0.011446 sps=14.022003 sps_per_gpu=3.505501 tps=918945.985503 tps_per_gpu=229736.496376 mfu=45.842940 train_loss=2.045786 val_loss=2.148510
[2024-07-17 07:45:27.797910][INFO][trainer:885] - step=240 loss=1.779287 dt=0.285465 dtf=0.005189 dtb=0.011220 sps=14.012250 sps_per_gpu=3.503062 tps=918306.793546 tps_per_gpu=229576.698387 mfu=45.844800 train_loss=2.045786 val_loss=2.148510
[2024-07-17 07:45:30.653597][INFO][trainer:885] - step=250 loss=1.704220 dt=0.289284 dtf=0.005471 dtb=0.010346 sps=13.827253 sps_per_gpu=3.456813 tps=906182.836379 tps_per_gpu=226545.709095 mfu=45.785926 train_loss=2.045786 val_loss=2.148510
[2024-07-17 07:45:33.512769][INFO][trainer:885] - step=260 loss=1.671318 dt=0.287679 dtf=0.005125 dtb=0.011250 sps=13.904380 sps_per_gpu=3.476095 tps=911237.442617 tps_per_gpu=227809.360654 mfu=45.758182 train_loss=2.045786 val_loss=2.148510
[2024-07-17 07:45:36.373461][INFO][trainer:885] - step=270 loss=1.650952 dt=0.298661 dtf=0.005118 dtb=0.011520 sps=13.393107 sps_per_gpu=3.348277 tps=877730.651421 tps_per_gpu=219432.662855 mfu=45.565875 train_loss=2.045786 val_loss=2.148510
[2024-07-17 07:45:39.236930][INFO][trainer:885] - step=280 loss=1.573242 dt=0.285970 dtf=0.005171 dtb=0.011290 sps=13.987477 sps_per_gpu=3.496869 tps=916683.279847 tps_per_gpu=229170.819962 mfu=45.587333 train_loss=2.045786 val_loss=2.148510
[2024-07-17 07:45:42.100605][INFO][trainer:885] - step=290 loss=1.533265 dt=0.286487 dtf=0.005432 dtb=0.011288 sps=13.962259 sps_per_gpu=3.490565 tps=915030.617828 tps_per_gpu=228757.654457 mfu=45.598392 train_loss=2.045786 val_loss=2.148510
[2024-07-17 07:45:44.964424][INFO][trainer:885] - step=300 loss=1.492064 dt=0.288480 dtf=0.005355 dtb=0.011480 sps=13.865774 sps_per_gpu=3.466443 tps=908707.340870 tps_per_gpu=227176.835218 mfu=45.576766 train_loss=2.045786 val_loss=2.148510
[2024-07-17 07:45:45.995833][INFO][trainer:820] - ['prompt']: 'What is an LLM?'
[2024-07-17 07:45:45.996497][INFO][trainer:824] - ['response']:

What is an LLM?

RICHMORD:
Char stire? how in those are name the range hone.

GLOUCESTER:
Nay, in lond's time the palt are worder more
That wilt in the purpose be a pey
And thou thine onter hands, and the which broth.

ELBOWINCA:
At lie my lord with the me an arms be a s
[2024-07-17 07:46:23.549987][INFO][trainer:760] - Saving checkpoint to: /home/foremans/tmp/polaris-talk/outputs/runs/pytorch/DDP/2024-07-17/07-42-13
[2024-07-17 07:46:23.550696][INFO][trainer:761] - Saving model to: /home/foremans/tmp/polaris-talk/outputs/runs/pytorch/DDP/2024-07-17/07-42-13/model.pth
[2024-07-17 07:46:25.496559][INFO][configs:141] - Appending /home/foremans/tmp/polaris-talk/outputs/runs/pytorch/DDP/2024-07-17/07-42-13 to /home/foremans/tmp/polaris-talk/2024-07-17-073327/wordplay/src/ckpts/checkpoints.log
[2024-07-17 07:46:28.374854][INFO][trainer:885] - step=310 loss=1.444200 dt=0.299907 dtf=0.005333 dtb=0.010637 sps=13.337481 sps_per_gpu=3.334370 tps=874085.133345 tps_per_gpu=218521.283336 mfu=45.384395 train_loss=1.495372 val_loss=1.713714
[2024-07-17 07:46:31.223079][INFO][trainer:885] - step=320 loss=1.429350 dt=0.285238 dtf=0.005245 dtb=0.011485 sps=14.023353 sps_per_gpu=3.505838 tps=919034.479880 tps_per_gpu=229758.619970 mfu=45.435743 train_loss=1.495372 val_loss=1.713714
[2024-07-17 07:46:34.074957][INFO][trainer:885] - step=330 loss=1.362220 dt=0.285027 dtf=0.005165 dtb=0.011407 sps=14.033736 sps_per_gpu=3.508434 tps=919714.904826 tps_per_gpu=229928.726207 mfu=45.485355 train_loss=1.495372 val_loss=1.713714
[2024-07-17 07:46:36.929464][INFO][trainer:885] - step=340 loss=1.350888 dt=0.284436 dtf=0.005199 dtb=0.011287 sps=14.062893 sps_per_gpu=3.515723 tps=921625.744709 tps_per_gpu=230406.436177 mfu=45.539549 train_loss=1.495372 val_loss=1.713714

wordplay: Example [video]

Figure 30: Training a LLM to talk like Shakespeare using saforem2/wordplay 🎮💬

❤️ Thank you!

  • Organizers

  • Feel free to reach out!

Acknowledgements

This research used resources of the Argonne Leadership Computing Facility, which is a DOE Office of Science User Facility supported under Contract DE-AC02-06CH11357

📓 References

References

Wei, Jason, Yi Tay, Rishi Bommasani, Colin Raffel, Barret Zoph, Sebastian Borgeaud, Dani Yogatama, et al. 2022. “Emergent Abilities of Large Language Models.” https://arxiv.org/abs/2206.07682.
Yang, Jingfeng, Hongye Jin, Ruixiang Tang, Xiaotian Han, Qizhang Feng, Haoming Jiang, Bing Yin, and Xia Hu. 2023. “Harnessing the Power of LLMs in Practice: A Survey on ChatGPT and Beyond.” https://arxiv.org/abs/2304.13712.
Yao, Shunyu, Dian Yu, Jeffrey Zhao, Izhak Shafran, Thomas L. Griffiths, Yuan Cao, and Karthik Narasimhan. 2023. “Tree of Thoughts: Deliberate Problem Solving with Large Language Models.” https://arxiv.org/abs/2305.10601.

Footnotes

  1. micro_batch_size = batch_size per GPU↩︎

  2. Efficient Large-Scale Language Model Training on GPU Clusters↩︎

  3. Source: Hannibal046/Awesome-LLM↩︎

  4. Figure from The Illustrated Transformer↩︎

  5. Figure from The Illustrated Transformer↩︎

  6. Video from: 🤗 Generation with LLMs↩︎

  7. Video from: 🤗 Generation with LLMs↩︎

Citation

BibTeX citation:
@unpublished{foreman2024,
  author = {Foreman, Sam},
  title = {Parallel {Training} {Methods}},
  date = {2024-11-05},
  url = {https://samforeman.me/talks/ai-for-science-2024/slides},
  langid = {en}
}
For attribution, please cite this work as:
Foreman, Sam. 2024. “Parallel Training Methods.” November 5. https://samforeman.me/talks/ai-for-science-2024/slides.