I've been baffled by Eclipse's extremely slow startup on my computers for quite some time. Today I decided to do another Google search on this problem and found this article https://www.genuitec.com/stop-slow-eclipse-myeclipse-startups/. It basically says the slowdown is caused by Windows Defender scanning the Eclipse folder and the workspace folder whenever Eclipse is started. I followed the instructions in the article to exclude those folders from Windows Defender, and the difference is literally night and day. If you want faster Eclipse startup, I highly recommend that you check out this article.