New answers tagged alternative
There are plenty of tools for this, here are a few with a GUI: xxdiff Meld * beediff KDiff3 * Diffuse * fldiff * They all do pretty much the same thing, but the first two possibly offer the best user experience. Those with an asterisk are available from Software Centre.
Normally I would recommend gnome-system-monitor for this, but that bug was filed in 2007 and hasn't been fixed yet. https://bugzilla.gnome.org/show_bug.cgi?id=499725 Anyway, if you need per-process I/O, you can try htop in the meantime; it's terminal based, but it doesn't require root access and with a little configuration it lets you sort by read/write ...
In Open Source realm, you can find many alternatives to what you want. I just want to point for something, don't ever treat applications as if they are the same, You can't find SAME alternative for Photoshop, instead you can find mostly all properties and maybe sometimes more but you have to learn how to use. Photoshop alternatives: gimp sudo apt-get ...
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