Zimbra performance issues highlight IE's inadequacies as web 2.0 platform

Yesterday I spoke with Zimbra CEO Satish Dharmaraj, to find out what's new in the Zimbra application and also to address some of the issues raised by ZDNet readers in my last post about Zimbra. "Zimbra is pushing the envelope of Ajax, whereas Gmail is a very light app" I'll review the new Zimbra features in my next post, but I want to devote this one to the performance issues raised by ZDNet readers.

If you recall in my last post, entitled Review of Zimbra - a feature-laden Web Office Suite contender, I concluded that Zimbra is an impressive collaboration suite chock full of functionality. However a few ZDNet readers noted some issues with the actual performance of Zimbra. jlanus_z said that while Zimbra's feature set is good, the usability falls short:

"...huge program successes are not about features but usability: the measure of the efficiency, efficacy and satisfaction users experiment when using them. Zimbra is succeeding in implementing an online software that behaves exactly like the desktop counterpart. This is the problem: most desktop applications suck; yes with great response times in some cases, but the user satisfaction is not sooo high except for a few exceptions."

ned.baugh said that "it's slick, and I hope it continues to develop, but I'd like to see an optimized client." Finally attardi noted:

"It maybe due to all those 3D gizmos, but the GUI is way too slow: it takes over 4 minutes to load on my old Pentium III, while GMail loads in < 10 seconds."

I put these questions, specifically the last one about the slowness of the UI, to Satish. He acknowledged there have been issues with IE browsers, in particular IE6. Satish said that Zimbra performs significantly better in Firefox, "primarily because of the DOM performance". He noted that Zimbra is "more of a DOM manipulator than Gmail is" - and because IE lacks decent DOM manipulation techniques, that's where they've had issues.

Furthermore Zimbra is "pushing the envelope of Ajax", said Satish, whereas "Gmail is a very light app and has a lot of HTML in it". Zimbra doesn't have anywhere near as much HTML, which hurts them in IE. Apparently IE7 will address these issues, so Satish is confident that Zimbra will not run into such problems in the new Microsoft browser.

Even so Satish said that since my last post in early April, the Zimbra team has addressed the performance issues in IE6. "It's still not ideal", said Satish, "[but] we're hoping the next version of IE will fix some of those issues." He noted in a follow-up email to me that "all of our customers are well past the IE 6 sluggishness issue - but it leads to some really nasty code hacks."

For more on this issue, see Zimbra staff member Ross Dargahi's blog post in April. He wrote:

"IE 6 is an inadequate platform for developing advanced Web 2.0 applications. I suspect that a number of hard core web application developers will nod their heads in agreement with this statement. From my experience, IE 6 is certainly more challenging to work with than some of its competitors, and it exhibits some very unpleasant behaviours that make it a difficult platform with which to develop advanced Web 2.0 applications."

He gets specific further into the post:

"From a Web 2.0 application developers perspective (developers who use a lot of JavaScript and DOM manipulaion), IE 6 is plagued by a number of well known problems such as its ability to readily leak memory."

Interestingly Ross sees this as a chance for Firefox to grab market share from Microsoft, because "Firefox’s superiority as a Web 2.0 platform" stands it in good stead as Ajax apps become "more ubiquitous and increasingly feature rich over time."

In my interview with Satish, he seemed confident IE7 would address some of the DOM manipulation issues that are affecting Zimbra. I hope so too, because I see a great future for feature-rich apps that push the envelope, like Zimbra and Morfik. It would be a real shame if Microsoft continued to hamper web 2.0 technology innovation by not upgrading its market-leading browser.