update readme

GETTING_STARTED.md

@@ -26,6 +26,12 @@ To train a model with "train_net.py", first setup up the corresponding datasets
 
 The configs are made for 1-GPU training.
 
+If you want to train model with 4 GPUs, you can run:
+
+```bash
+./tools/train_net.py --config-file ./configs/Market1501/bagtricks_R50.yml --num-gpus 4
+```
+
 To evaluate a model's performance, use
 
 ```bash

README.md

@@ -5,6 +5,7 @@ FastReID is a research platform that implements state-of-the-art re-identificati
 ## What's New
 
 - [Jul 2020] Distributed training with multiple GPUs, it trains much faster.
+- [Jul 2020] `MAX_ITER` in config means `epoch`, it will auto scale to maximum iterations.
 - Includes more features such as circle loss, abundant visualization methods and evaluation metrics, SoTA results on conventional, cross-domain, partial and vehicle re-id, testing on multi-datasets simultaneously, etc.
 - Can be used as a library to support [different projects](https://github.com/JDAI-CV/fast-reid/tree/master/projects) on top of it. We'll open source more research projects in this way.
 - Remove [ignite](https://github.com/pytorch/ignite)(a high-level library) dependency and powered by [PyTorch](https://pytorch.org/).