

Post-mortem on New Relic's Move to Ruby 1.9 - whalesalad
http://blog.newrelic.com/2012/10/23/eating-the-1-9-elephant

======
dguaraglia
Hey, "post-mortem" means "after death" in Latin. Maybe we should start
introducing some variety, for example the much more accurate "post-facto"?

It's kinda weird clicking on an article about the "post-mortem" analysis of a
startup launch to find out it's doing good after all :)

------
venus
I can only guess at what horrors lie below New Relic's calm waters that it
took them 8 months to convert their code to 1.9. It's not _that_ different! I
have generally flipped over to 1.9 as part of Rails 3 upgrades, the rails part
being far more work than the ruby part.

What on earth were you doing that took so long? Is it because NR's requirement
to parse a lot of log files, so the changes to strings had outsize impact?

~~~
intjonathan
You're right, it's not that different - what killed us was unsupported gems
that were wired deeply into our system, along with operations weaknesses that
made changing ruby versions extremely challenging.

We took extra time to refactor those weaknesses out, so future changes like
this one will be much simpler.

Incidentally, we don't parse log files - our agents send Thrift, JSON, and
Ruby Marshaled data. String changes affected us a little bit, but the vast
majority of the code in that tier is Java anyway. Only the front-end code is
in Rails anymore.

------
dansingerman
Not sure 'Post-mortem' sets the right tone given the contents of the post.

~~~
envex
That's generally the term used when someone is looking back and writing about
something.

Don't quote me on that though.

~~~
jemka
Not just "something", but something that has "died" or ceases to exist in its
prior form and the "postmortem" is generally the detailed analysis of what
happened.

Also, <http://www.merriam-webster.com/dictionary/postmortem>

~~~
Argorak
The second definition given does not refer to "death" at all and is commonly
used in science and business contexts. It usually refers to the project (or
the "event") being over at the point of discussion.

The term is overloaded nowadays, as can be seen on Wikipedia:
[http://en.wikipedia.org/wiki/Post-
mortem_%28disambiguation%2...](http://en.wikipedia.org/wiki/Post-
mortem_%28disambiguation%29)

------
jaggederest
I always thought the 1.9 GC instrumentation was a little wonky. Glad they got
that cleared up.

~~~
intjonathan
We had the same suspicion but only one customer had observed it repeatably in
the wild. We turned out to be customer number two. :) If you're running 1.9,
definitely get agent 3.5 as soon as you can.

~~~
jaggederest
Ha, no I was the agent developer who put the GC instrumentation in for 1.9 :)
back in 'the day'

