Question: Is there a limit to the number of parallel Docker push/pulls you can do? 

> 
> E.g. if you thread Docker pull / push commands such that they are
>  pulling/pushing different images at the same time what would be the
>  upper limit to the number of parallel push/pulls
> 
> 
> 

Or alternatively

> 
> On one terminal you do docker pull ubuntu on another you do docker
>  pull httpd etc - what would be the limit Docker would support? 
> 
> 
>

Answer: 
The options are set in the configuration file (Linux-based OS it is located in the path: /etc/docker/daemon.json and C:\ProgramData\docker\config\daemon.json on Windows)

Open /etc/docker/daemon.json (If doesn't exist, create it)

Add the values(for push/pulls) and set parallel operations limit

```
{
    "max-concurrent-uploads": 1,
    "max-concurrent-downloads": 1
}

```

Restart daemon: `sudo service docker restart`
For anyone using Docker for Windows and WSL2:
You can (and should) set the options on the Settings tab:

[Docker for Windows Docker Engine settings](https://i.stack.imgur.com/S52iG.png)