Update 3d model building with VSFM on the command line.md

workshop materials/3d model building with VSFM on the command line.md

@@ -96,6 +96,8 @@ That command runs the entire process. Depending on the complexity of the images
 
 + 'segmentation error'
 
+> Boot2docker:
+
 You might get a 'segmentation error' right at the start. What gives? It could be a memory issue. On the mac, use the 'go to' folder command in Finder to go `/users/[user]/.boot2docker` then make a new file there (with no extension) called `profile`. Put something like this in, as is appropriate for your system:
 
 ```
@@ -106,6 +108,12 @@ DiskSize = 20000
 Memory = 7168
 ```
 
+> Docker-tools, Kitematic etc:
+
+Find the `config.json` file inside the `.docker` folder on your machine (ie, `/users/[user]/.docker/machine/machines/default/config.json`
+
+Inside that is a setting for memory. Open it in a text editor, ramp up the memory (as much as you've got) in mb, save. Then you need to [restart the virtual machine](https://docs.docker.com/machine/reference/restart/). This should do the trick. It didn't seem to do it for me, until at one point I started the Kitematic gui, and was rewarded with a 'building vm'.
+
 [WINDOWS?]
 
 So, make sure your images or that video are safe on your host machine somewhere. Exit your docker container and restart docker and the vsfm container. You can then drop your images back in.