Bill Gates is famous for having said we will never need more than 640KB RAM on a personal computer. However if you ask someone today whether say 18GB of RAM is enough for a development workstation, what do you think the answer would be?

I am sure most people would argue even if you run 3 VM's each using 2GB RAM, and an IDE and mail and browsers and Word and whatever, you will not easily exceed 10GB of RAM. So it should be more than enough.

Well - here is the problem. I have 18GB RAM. I regularly exceed that limit and start swapping like mad even if I only have 2 VM's open - each using 2GB of RAM, IntelliJ, several small apps. The reason? Nobody can write leak free code. Not Microsoft, not Apple, not the people behind OSS software. Applications, kernels, drivers - they all leak eventually. So the question becomes not whether x GB of RAM is enough, but rather how long uptime can I achieve with a given amount of RAM. I found that I cannot exceed 27 days of uptime before I have to reboot to reset all the leaks. This is on my Mac Pro 8 core.

What is your uptime limit for the amount of RAM you have?