Train Model has been running for past 30 mins for only 5 training image for each Tag. I have 2 tags

> Please provide us with the following information:
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### This issue is for a: (mark with an `x`)
```
- [X] bug report -> please search issues before submitting
- [ ] feature request
- [ ] documentation issue or request
- [ ] regression (a behavior that used to work and stopped in a new release)
```

### Minimal steps to reproduce
> I have tried to train a model with 2 tags and 5 images per tag .. train model has been running for the past 30 mins without any sign of getting closed.

### Any log messages given by the failure
>

### Expected/desired behavior
> 10 images training should not take a lot of time.

### OS and Version?
> Windows 7, 8 or 10. Linux (which distribution). macOS (Yosemite? El Capitan? Sierra?)

### Versions
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### Mention any other details that might be useful

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> Thanks! We'll be in touch soon.

首先，使用两个标签、每个标签五张图像来复现训练，并记录操作系统、版本和所有日志。调查训练过程在哪个环节仍保持活动状态，并将其行为与十张图像的预期完成情况进行比较。完成的标准是确定原因，并且训练运行完成或报告明确的失败。

由索引模型根据 Issue 内容生成。