GPU SDK Correspondence and Device Targeting Table

GPU Targets Table

OpenCL is a universal massively parallel programming framework that targets to multiple backends (GPU, CPU, FPGA, etc). Bascially, to use a device from a vendor, you have to install drivers from that specific vendor. Intel and AMD’s OpenCL runtime also include x86 CPU target support. NVIDIA’s OpenCL runtime only supports NVIDIA GPU (No CPU support). In general, OpenCL CPU backends are quite slow, and should be used for testing and debugging only.

You can find below a table of correspondence:

SDK CPU Intel/AMD GPU Intel GPU AMD GPU NVIDIA
Intel SDK for OpenCL Supported Supported Not Supported Not Supported
AMD APP SDK * Supported Not Supported Supported Not Supported
NVIDIA CUDA Toolkit Not Supported Not Supported Not Supported Supported

Legend:

* AMD APP SDK is deprecated. On Windows, OpenCL is included in AMD graphics driver. On Linux, newer generation AMD cards are supported by the ROCm driver. You can download an archived copy of AMD APP SDK for Linux from our GitHub repo.

Query OpenCL Devices in Your System

Your system might have multiple GPUs from different vendors (“platforms”) installed. Setting up LightGBM GPU device requries two parameters: OpenCL Platform ID (gpu_platform_id) and OpenCL Device ID (gpu_device_id). Generally speaking, each vendor provides a OpenCL Platform, and devices from the same vendor have different device IDs under that platform. For example, if your system has an Intel integrated GPU and two discrete GPUs from AMD, you will have two OpenCL platforms (with gpu_platform_id=0 and gpu_platform_id=1). If the platform 0 is Intel, it has one device (gpu_device_id=0) representing the Intel GPU; if the platform 1 is AMD, it has two devices (gpu_device_id=0, gpu_device_id=1) representing the two AMD GPUs. If you have a discrete GPU by AMD/NVIDIA and an integrated GPU by Intel, make sure to select the correct gpu_platform_id to use the discrete GPU as it usually provides better performance.

On Windows, OpenCL devices can be queried using GPUCapsViewer, under the OpenCL tab. Note that the platform and device ID reported by this utility start from 1. So you should minus the reported IDs by 1.

On Linux, OpenCL devices can be listed using the clinfo command. On Ubuntu, you can install clinfo by executing sudo apt-get install clinfo.

Examples

We provide test R code below, but you can use the language of your choice with the examples of your choices:

library(lightgbm)
data(agaricus.train, package = "lightgbm")
train <- agaricus.train
train$data[, 1] <- 1:6513
dtrain <- lgb.Dataset(train$data, label = train$label)
data(agaricus.test, package = "lightgbm")
test <- agaricus.test
dtest <- lgb.Dataset.create.valid(dtrain, test$data, label = test$label)
valids <- list(test = dtest)

params <- list(objective = "regression",
               metric = "rmse",
               device = "gpu",
               gpu_platform_id = 0,
               gpu_device_id = 0,
               nthread = 1,
               boost_from_average = FALSE,
               num_tree_per_iteration = 10,
               max_bin = 32)
model <- lgb.train(params,
                   dtrain,
                   2,
                   valids,
                   min_data = 1,
                   learning_rate = 1,
                   early_stopping_rounds = 10)

Make sure you list the OpenCL devices in your system and set gpu_platform_id and gpu_device_id correctly. In the following examples, our system has 1 GPU platform (gpu_platform_id = 0) from AMD APP SDK. The first device gpu_device_id = 0 is a GPU device (AMD Oland), and the second device gpu_device_id = 1 is the x86 CPU backend.

Example of using GPU (gpu_platform_id = 0 and gpu_device_id = 0 in our system):

> params <- list(objective = "regression",
+                metric = "rmse",
+                device = "gpu",
+                gpu_platform_id = 0,
+                gpu_device_id = 0,
+                nthread = 1,
+                boost_from_average = FALSE,
+                num_tree_per_iteration = 10,
+                max_bin = 32)
> model <- lgb.train(params,
+                    dtrain,
+                    2,
+                    valids,
+                    min_data = 1,
+                    learning_rate = 1,
+                    early_stopping_rounds = 10)
[LightGBM] [Info] This is the GPU trainer!!
[LightGBM] [Info] Total Bins 232
[LightGBM] [Info] Number of data: 6513, number of used features: 116
[LightGBM] [Info] Using GPU Device: Oland, Vendor: Advanced Micro Devices, Inc.
[LightGBM] [Info] Compiling OpenCL Kernel with 16 bins...
[LightGBM] [Info] GPU programs have been built
[LightGBM] [Info] Size of histogram bin entry: 12
[LightGBM] [Info] 40 dense feature groups (0.12 MB) transfered to GPU in 0.004211 secs. 76 sparse feature groups.
[LightGBM] [Info] No further splits with positive gain, best gain: -inf
[LightGBM] [Info] Trained a tree with leaves=16 and max_depth=8
[1]:    test's rmse:1.10643e-17
[LightGBM] [Info] No further splits with positive gain, best gain: -inf
[LightGBM] [Info] Trained a tree with leaves=7 and max_depth=5
[2]:    test's rmse:0

Running on OpenCL CPU backend devices are in generally slow, and we observe crashes on some Windows and macOS systems. Make sure you check the Using GPU Device line in the log and it is not using a CPU. The above log shows that we are using Oland GPU from AMD and not CPU.

Example of using CPU (gpu_platform_id = 0, gpu_device_id = 1). The GPU device reported is Intel(R) Core(TM) i7-4600U CPU, so it is using the CPU backend rather than a real GPU.

> params <- list(objective = "regression",
+                metric = "rmse",
+                device = "gpu",
+                gpu_platform_id = 0,
+                gpu_device_id = 1,
+                nthread = 1,
+                boost_from_average = FALSE,
+                num_tree_per_iteration = 10,
+                max_bin = 32)
> model <- lgb.train(params,
+                    dtrain,
+                    2,
+                    valids,
+                    min_data = 1,
+                    learning_rate = 1,
+                    early_stopping_rounds = 10)
[LightGBM] [Info] This is the GPU trainer!!
[LightGBM] [Info] Total Bins 232
[LightGBM] [Info] Number of data: 6513, number of used features: 116
[LightGBM] [Info] Using requested OpenCL platform 0 device 1
[LightGBM] [Info] Using GPU Device: Intel(R) Core(TM) i7-4600U CPU @ 2.10GHz, Vendor: GenuineIntel
[LightGBM] [Info] Compiling OpenCL Kernel with 16 bins...
[LightGBM] [Info] GPU programs have been built
[LightGBM] [Info] Size of histogram bin entry: 12
[LightGBM] [Info] 40 dense feature groups (0.12 MB) transfered to GPU in 0.004540 secs. 76 sparse feature groups.
[LightGBM] [Info] No further splits with positive gain, best gain: -inf
[LightGBM] [Info] Trained a tree with leaves=16 and max_depth=8
[1]:    test's rmse:1.10643e-17
[LightGBM] [Info] No further splits with positive gain, best gain: -inf
[LightGBM] [Info] Trained a tree with leaves=7 and max_depth=5
[2]:    test's rmse:0

Known issues:

  • Using a bad combination of gpu_platform_id and gpu_device_id can potentially lead to a crash due to OpenCL driver issues on some machines (you will lose your entire session content). Beware of it.
  • On some systems, if you have integrated graphics card (Intel HD Graphics) and a dedicated graphics card (AMD, NVIDIA), the dedicated graphics card will automatically override the integrated graphics card. The workaround is to disable your dedicated graphics card to be able to use your integrated graphics card.