mPulse

Friday, May 30, 2008

The Twitter Debate - YATPBP

Yes, it's YATPBP (Yet Another Twitter Performance Blog Post).

About 10 days ago, I turned GrabPERF loose on Twitter. Now before you accuse this of crippling the service and bringing it to its knees, realize that GrabPERF simply requests a document over HTTP about two times a minute. No additional requests are made for images and the like.

In the ocean of requests coming into the Twitter systems, the GrabPERF requests are like individual water molecules being added to the pool.

Twitter - Public RSS Feed, 1Day


The above graph shows performance for the last 24 hours. The purple dots are errors. Complete details, and a dynamically updating graph, can be found here.


Now that I have had a chance to show off, I will leave the Twitter team in peace. I am not a developer or a systems expert. I, like most people, rely on people with specialized skills to analyze and resolve the problem. There are many people on the Web who have taken on the challenge of reverse-engineering Twitter to try and determine how it does what it does, and how they would build a better mousetrap.


Ok. Go do it. Or shut up and let the Twitter team get down to the hard work of making this service work. Or volunteer to help them fix the problems.


The Twitter team has stated that they know how to resolve the issues that are at the heart of the performance issue. But as I said in a comment to @gapingvoid tonight, knowing what the solution is only makes up 15% of the application development process. Building, testing, deploying and verifying the solution takes 85% of the effort.


The Twitter team has a lot of work ahead of them. Buy them beer and pizza and let them get to it.

Thursday, May 8, 2008

It's the network, dummy

In the GigaOm blog today, Allen Leinwand puts up a monstrous wake-up call to all the hip and cool Web 2.0 companies out there: Your apps run across the Internet [here].

I have spent 9 years investigating, diagnosing, and validating the Web performance issues of companies. I can tear the Web performance data of a site down quickly and ask pointed questions about why certain components of an application are behaving poorly.

But even after 9 years, there are still gimme problems around connection setup that I can seem brilliant about, not because I have some secret knowledge, but because I think of Web performance from the Network UP, not from the Application DOWN.

The subtlety of this difference what Leinwand is alluding to. Fancy applications run across the Internet. The Internet is built on TCP. And TCP is built on-top of a very complex networking infrastructure that is way beyond the realm of my skills.

If you don't know what packet loss looks like, or how your fancy app presents to clients, or how to ensure that this data is collected and presented to you in a timely way, then you are being exposed to alerting by client calls.

All because you thought the biggest problem was scaling your app, not ensuring that the network it crossed to reach people affected the way it performed. Network geeks created Web 1.0; Web 2.0 seems to think they are mostly unecessary.

Wrong.

Measure your performance. Understand TCP. Hire a network geek (or 20).

Then sleep better at night.

Monday, May 5, 2008

Xobni Public

If you've come here looking for Xobni invites, don't bother. It's open to all now.

Go make your Outlook less excruciating.

Friday, May 2, 2008

Xobni Invites

Got six of them. FIFO.

Gone!

My first week with the Blackberry Pearl 8100

Last week a colleague, who had been forced by corporate policy to switch to a Verizon Treo, donated his Blackberry Pearl 8100 to me.

It was a Cingular/ATT locked phone. I unlocked it, stuck my T-Mobile card into it, and upgraded my plan to the unlimited data plan. I the MIS department at work add an Exchange redirect of my work mail to the Blackberry-provided email address (Blackberry Enterprise Services are evil), so that I could claim a real work usage for this. But there is also a personal email on it (and you will have to ask me for that one!).

[Author Sidebar: Two days later, I managed to lose my T-Mobile Z3 Rizr. Lose. Like can't find. Likely in the hands of another happy user who has figured out the GSM thing. I am an idiot.]

What is my main purpose for this thing? I previously had not had email on my mobiles. This restricted (prevented) my ability to use services like Flickr, BrightKite, TwitPic among others. Also, I can add services such as Google Maps and other mobile apps for the Blackberry. Still waiting for Skype for the non-wifi Blackberry.

My opinion thus far is positive. While there are obviously newer and better smartphones out there now, but the Pearl meets my needs for now. And the price (donation free!) was definitely within my budget. I am still adjusting to the 3/4 QWERTY keyboard, but it is not anymore difficult than MOTO's intellitype (yeah, I know it's a stretch) system.

Will keep you updated on my joy/frustration factor.

Thursday, May 1, 2008

To dream...yeah, right

Well, back to dreaming.

It (very briefly) looked like I might be able to get my MacBook Pro (a constant whining theme here). But, again, it fell through. Reality kicked in and the money went to where it was really needed.

Maybe I'll score a consulting gig or something to help with this...

Leads on cheap MacBook Pros appreciated.

And remember, I will work/blog/twitter/pimp for geek cred computing style.