Clearing up some things about LinkedIn mobile’s move from Rails to node.js

> And those requirements kept growing. If my calculations are correct, the standard setup for engineers now is a machine with 20 or more gigabytes of RAM just to RUN the software.

Close. In 2011, all the engineer desktops got upgraded to 36Gigs. At the time, the eng department still hadn't figured out how to deploy without duplicating hundreds of jar files everywere.

This sounds much more sane than "node is 20x faster than rails", thanks for validating the assumption most of us were making.

This is a great post for validating management concerns about pulling in sexy new technologies for the hell of it. Every place I've worked I've been unable to convince management to use e.g. Rails (5 years ago) or node.js (recently). Even though I love these technologies and wish I'd had more time in full-time employment to learn and play with them, I understand and appreciate the risks implicit with adopting a shiny new technology in your company's IT dev/production environments.

It's also a great post illuminating how in hindsight some things can be really obvious (that building a high capacity web service dependent on a single-threaded server will give you problems down the road), but at the time it's not always easy seeing the woods for the trees.

For me though, the big takeaway was that one line summary: "You’re comparing a lower level server to a full stack web framework." Node.js has a pretty nice library/module ecosystem now, but for a complete full-stack solution with maximum productivity I would venture that there is nothing out there that compares to Rails currently.

It's definitely true, that node.js isn't a full fledged framework, but I still wrote several projects using it and you know what? I don't regret it, as much as I don't regret my move from C++ to C over the past years. And for the memory usage: Yes, even my biggest project never needed more than 100MB of RAM (when not using the cluster module).

But I completely agree with "the rewrite thing". I guess the other factors made it necessary to still do it....

I met Ikai through the Silicon Valley Rails Meetup, which I co-hosted back in 2008-2009 and which met at LinkedIn HQ in Mountain View. This post is a great contribution to the recent discussion about Rails at LinkedIn, and I hope it gets the attention it deserves.

The concept that I got from the main article was that they tailored their application for "long-lived connection" to avoid multiple resource calls to make their web server more responsive. They also mention things like using "aggressive cacheing", "storing templates locally", "using timestamps to stream only required resources", "rearchitecture and rewrite."

Never once did I ever feel this article was advising that node.js was superior to RoR - they only every justified, at a high level, a way better approach (in terms of server load) to an "MVC" like architecture by leveraging client side frameworks and technique to lessen server load.

The author of this article also makes it clear at the end by stating that comparing the solutions is apples to oranges, but so did the original article...so I don't get the need for "clarification".

EDIT: I retract my "way better" statement - I mean "way better" in the sense of server load.

And the blog-to-commentary-to-blog cycle begins anew.

Mongrel isn't and wasn't single-threaded. Rails was.

"•Firefighting? That was probably a combination of several things: the fact that we were running MRI and leaked memory, or the fact that the ops team was 30% of a single guy."

:o That may explain why they had spam and security issues.

Node.js is old news. Time to move on to GoLang. :)

Wow, linkedin sounds like a place I really want to work!

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