Maybe try to disable swap-memory, and see then if there is enough RAM still?

In Android, if an app is well written, it can resume from the pause stage as well at it could resume from swapped stage in an OS where swap memory is enabled. But there is lazy coders both in Android and outside Android.

In Android SGS3, I find 1 GB RAM is not enough,
when I have Firefox with 10 tabs open, and for example music player (mp3, ac4, vorbis) in the bacground playing music and I want to take a photo with the camera. After the photo has been taken and I return to Firefox, I notice it hasn't stayed alive in the background but gone to Androids "pause"-stage, because FF has failed to keep the session data alive for some web-page. (FF could do better though.)

Doing the same with Galaxy S4 (2 GB RAM) does not put a FF with 10 tabs to pause stage but it stays alive. So extra 1 GB RAM in S4 helps in this use case. I haven't checked how much extra RAM over 1 GB would actually work. And yes, FF for Android is abit bloated.

The problem manifests itself also when PasswdSafe application is used with FF which has ~10 tabs open. Sometimes when there are also other apps open in the background, happens this:
1) a web page requires a login+password.
2) I open PasswdSafe and give the master password.
3) Username is fetched from PasswdSafe-app,
4) then pasted to FF,
5) then password for the site is wanted to be copied from the PasswdSafe, but the app has been pause'd in the background, and when resumed the app "behaves badly" and asks for the main password, again.
The app PasswdSafe doesn't actually behave badly, because it cannot really trust filesystem and keep the encrypted password database open during the Android pause-stage. It could not trust the swap-partition either if the process would be swapped there. I do not remember how in N900 this was, was PasswdSafe allowed to be swapped out.

Ofcourse, having 10 tabs and web sites open in Firefox may not be the smart thing to do. But I tend to forgot I am using a phone and not a PC. People use tabs also in mobile devices just because they can.

Now in the Jolla's first device, when both Qt and Android stacks are loaded and a user multitasks both Android apps and Qt apps, having just 1 GB may cause problems.

Also when using multiwindow multitasking in Android devices, it helps to have more RAM:
http://www.youtube.com/watch?v=nJ4iQudfdSk (2m 16s)
I must say, Galaxy Note3 (3 GB RAM) has the best multi tasking currently as seen in the video. Note3 can run Qt-apps as well.

Multiwindow+multitasking is something which should be in Sailfish also eventually.