Create AVD with Eclipse: Memory Options, Internal Storage, SD Card

Question

I am creating a new AVD within Eclipse, Android dev. tools 21.0, and it would be great to have some explanation on
"Memory Options" (RAM and VM Heap), "Internal Storage" , and "SD card".
(I am sorry but since I am a new user I am not allowed to post a snapshot image)

I would need:
- the meaning
- the unit of measure (for RAM and VM heap are not displayed)
- criteria to choose the values

Thanks

Answer 1

First to clear up some possible confusion, Eclipse doesn't exactly have its own AVD creation mechanism. It has a plug-in which calls the Android Vitrual Device Manager. The AVD Manager can also be accessed from the command line using "android avd", and comes as part of the Android SDK (so this question isn't specific to Eclipse users).

As for the definitions:

• Internal storage
  • Built-in, non-removable file storage capacity. The operating system and most apps will be installed here. When you see a device advertised with 8GB or 16GB, this is what that number refers to.
  • The AVD Manager allows you to select Gigabyte or Megabyte.
  • The choice is up to your needs and the amount of space you have on your hard drive, but you'll probably want a bare minimum of 200MB. 2GB will probably be more than enough. If you run out of space you can always add more or move files to the SD card.
• SD card
  • Similar to Internal storage, but refers to the storage an Android device would have access to on a removable memory card (the same kind of card digital cameras use). This is the place for storing user files, including documents, music and video, but some applications are built to be stored here.
  • The AVD Manager allows you to select Gigabyte, Megabyte, or Kilobyte.
  • Again, this uses space on your computer's hard drive, but this value is completely optional. You can safely leave this blank until you need to test how your app uses external storage.
• Memory Option- RAM
  • Available working memory, used by the operating system and any running applications. This directly affects how many apps can be loaded at the same time.
  • The AVD Manager expects a value in MB.
  • This uses your computer's RAM, which is a limited resource so you don't want to use too much. I'd say the current range to play with is 256MB to 2024MB, so your sweet spot is likely either 512 or 1024.
• Memory Option- VM Heap
  • This is a more advanced topic which is way out of scope of a beginner question. For simplicity's sake I'll just say that where RAM is related to the sum of running apps, Heap is related to an memory available to each individual app.
  • The AVD Manager expects a value in MB here as well.
  • For a reasonable value, refer to this question which lists real-world values: Android heap size on different phones/devices and OS versions
  • For much more information on memory, refer to the Android Developer site (http://developer.android.com/training/articles/memory.html)