Arch x64, KDE 4.10.3, firefox open with 7 tabs (3 are active thanks to Unload-- https://addons.mozilla.org/en-US/fir...don/unloadtab/). I did just close a lot of tabs about 5minutes ago though so maybe its not de-allocated that memory yet. Firefox is using the most memory, followed by virtuso (Nepomuk). A big chunk of that is probably in use by zRAM-- https://wiki.archlinux.org/index.php...cache_.2F_Zram.
And I can hit memory-pressure on occasion, mostly during compiles (/tmp is tmpfs with 3G alloted because im on an SSD and I didnt want to wear it out), hence 4GB of swap, and zRam.