This is more on my experience with my Galaxy Player with Android Gingerbread.
I started getting warnings that a database was getting full on the device. I looked and I have plenty of storage left when I look at various settings. Finally at one point I stopped receiving chats through Google Talk and email through Google Gmail. The weird thing was that the device seemed to know I was receiving emails, but wouldn't show them in the app. It would say new email in Gmail and would open Gmail when I would click on the notification, but it would not show me any current messages.
It didn't occur to me that they were related, since the message stopped coming up. I also had just installed a new power manager Juice Defender. I was running along with the previous power manager I was using, Advanced Task Killer. I assumed that one or both of these were the problem or their interaction together, since I had seen settings in Juice Defender talking about disabling WIFI and other stuff. The thing was that no other program was having problems getting notifications and WIFI was showing on and connected.
I uninstalled Juice Defender and Advanced Task Killer and it did not fix the problem. I was just about to uninstall Gmail and Talk when I noticed a setting on the screen where I would uninstall that said clear all messages. At that point I remembered the full database message. I figured that it would redownload the last 30 days of messages after I dumped the cache and I was going to blow away the app and start fresh anyway, so I figured there was no harm and in reality less harm than starting over.
I cleared the emails and loaded the Gmail app. BAM! Empty inbox. Then a few moments later recent messages showed up.
I am still uncertain as to what I filled up when the device showed plenty of space, but for now I am back in business.
Not sure if this is a Gingerbread problem, but I really want Jelly Bean, especially after using it on my wife's Nexus 7.