On December 8, 2005, we published a story that wondered: Firefox 1.5: Not Ready For Prime Time? In response, some 450 (and climbing) InternetWeek, InformationWeek, TechWeb Pipelines, and Scot's Newsletter readers have sent details about their experiences with Firefox 1.5. A picture is emerging about Firefox 1.5 in the real world -- on a small percentage of Windows, Mac, and Linux computers -- that is less than positive.

			In This Article • Reports Of Problems • Some Examples From Readers • Memory, CPU, And Stability Woes • Mozilla's Response • Can Bfcache Be The Problem? • Pushing The Memory Envelope • Whose Fault?

Before we get too far down that path, however, let's put things in perspective. More than 60 percent of the people who responded to our request for personal experiences with Firefox 1.5 reported they had no problems whatsoever with the browser software. And there is absolutely no statistically valid way to draw any hard conclusions about how many people are having stability issues with Firefox 1.5 based on this small sample size. At a rough guess, the number of people experiencing serious problems is probably well under 10 percent of all the people who have downloaded and installed Firefox 1.5.

Nevertheless, the people who are experiencing problems aren't having fun. And a lot of our readers are reporting the same woes:

• Firefox's use of physical and virtual memory is exceptionally high.
• CPU usage spikes to 100 percent (usually while loading a Web page).
• The browser freezes up for seconds, minutes, or permanently.
• The browser won't launch until they remove an errant "firefox.exe" process in Task Manager.
• The browser crashes suddenly (usually while loading a Web page).
• The browser has trouble loading specific pages, but there's no commonality among users as to which pages won't load.
• The initial launch of Firefox loads slower.
• Third-party application hyperlinks (such as a link in an e-mail message) take a long time to open a new Firefox tab or to launch the browser.

Memory spikes like these caused us to look more closely into Firefox's use of virtual and physical memory. (Click to enlarge image.)