From my experience, if you look at 'free -h' printout after some long time of system operation, you need to have at least as much 'free' in 'Swap' as you have 'used' in 'Mem'. And if your swap is full, that is, if you have 0 'free' in 'Swap', you should definitely increase your swap space. Initially...

Dear all, I see this item on AliExpress : http://www.aliexpress.com/item/Portable-Double-USB-30000mAh-Power-Bank-Backup-Battery-Pack-With-EU-Adapter-Supply-Recharge-External-Free/830909945.html What I think I need, is a kind of UPS, normally connected to 220v AC mains, preferably with multiple 5v 1A...