
EC2 Users Should be Cautious When Booting Ubuntu 10.04 AMIs - mike_heffner
https://silverline.librato.com/blog/main/EC2_Users_Should_be_Cautious_When_Booting_Ubuntu_10_04_AMIs
======
mihasya
We ran into what we believe to be this very problem at SimpleGeo and spent a
long time figuring out what the cause of the JVM locking up for tens of
minutes at a time were; we believe this bug (or general class of bugs) to be
responsible. Upgrading to 10.10 has caused the majority of the symptoms to
disappear.

My personal hunch is that there are probably startups and developers that
dumped Cassandra due to "stability issues," which were in reality symptoms of
this bug. There's obviously no way of confirming or denying this, so I'll
reiterate that it's just a hunch.

~~~
gary4gar
Instead of 10.10, I would suggest switching to Debian Or CentOS.

Due its short support cycle, Maverick isn't suited for servers.

~~~
mihasya
You're neglecting the fact that which distro you choose has a large influence
on the kernel version you get to run. With the amount of work going into
stabilizing the kernel when running in a virtualized environment, chaining
yourself to a slow-moving distro will cause the exact opposite of stability
when running on Xen. See: this blog post.

~~~
jerf
Recompiling a Linux kernel with a custom patch is in the core set of skills
that I would expect any Linux admin to have. It's not that hard. It's not even
that hard to take existing distro kernels and add a patch to them, and
maintain your patch going forward as the distro continues their refinements.

When you have Linux on your server, you _own_ it. You can do whatever you
want. The distro is the beginning of your power, not the end of it. If you're
running a Linux server and you currently have the attitude that you are boxed
in by your distro I recommend that you immediately dig into the relevant
packaging system and learn enough to put your own patch on top of any existing
software package, and recreate the package in the relevant manner (new RPMs,
new .deb, whatever).

(Yes, there's a cost/benefit tradeoff to each such patch you have to carry on,
but there is still economic value merely in _having_ the option.)

~~~
nupark2
It's 2011, and screwing around with kernel compilation is a waste of my time.
It should 'just work'.

The only time I recompile a kernel is when I'm working on kernel code. If UNIX
distributions are doing their jobs, a _sysadmin_ should never have to touch
it.

~~~
jerf
It's 2011. _Everything_ should just work.

Alas.

------
aaronblohowiak
librato has an amazing product and continues to have a great blog. I love how
they dig into the root cause (linking to the typo in the patch that introduced
the bug) and also have easy graphs to take in the impact.

------
mey
Is this strictly a Ubuntu/Xen bug, or does this have impacts on other VM
environments (Virtual Box/VMWare)?

------
RyanKearney
Honestly if you're using Ubuntu for a server then performance is not your
priority anyway.

~~~
mihasya
What is your recommendation?

~~~
RyanKearney
CentOS if you can't use RHEL.

~~~
mihasya
Do you have some benchmarks handy that indicate that CentOS or RHEL are more
performant than Ubuntu?

~~~
maratd
Any performance differences should be negligible. Use what you're used to. I
personally use Amazon/CentOS/RHEL because I know where everything is and how
everything goes.

~~~
mihasya
;)

------
dreamdu5t
This applies to any AMI, Ubuntu or not.

Ubuntu shouldn't be used for web servers to begin with. You should be using a
distribution with a long and thorough stable release cycle with minimal
packages, such as Debian.

~~~
krobertson
Can you clarify? I wouldn't use non-LTS on servers, but the LTS ones have a
stable and long enough shelf life.

I've personally found Ubuntu more bare bones out of the box than CentOS.

~~~
dreamdu5t
The main difference between Ubuntu-LTS and Debian is that Debian's stable
release cycle is longer and more thorough. This means that Ubuntu-LTS will
have slightly newer software, but Debian will likely have less bugs.

Debian's primary concern with its release cycle is stability. Other
distributions like Ubuntu or CentOS trade a little stability for newer
software.

My method: Use Debian but when you _must_ have newer versions just add an
unofficial repository to your apt sources (assuming you're prepared to deal
with the complexity and inconsistency this might introduce).

~~~
jsight
> The main difference between Ubuntu-LTS and Debian is that Debian's stable
> release cycle is longer and more thorough.

I believe that the debian stable release cycle is currently at about 2 years,
w/ a very short support cycle afterwards. The LTS cycle is 2 years with a 3
years of additional support afterwards.

~~~
krobertson
I have to agree more there. We recently moved from Debian to Ubuntu and like
it far more.

