

Ask yc.news: Opinions on EC2? - davidw

I'm looking into Amazon's EC2 "web service", and I'm wondering if anyone else here has looked at/utilized it.  What are its strengths and weaknesses?  What did you use it for?  What should it not be used for?
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kirubakaran
I use EC2 and I do swear by it. I see the initial extra effort you need to put
in to get it to work right (designing for failover etc) as: 'the more you
sweat in practice, the less you bleed in battle'.

I first ported a toy app that I wrote (<http://www.instantwordsearch.com>) to
EC2 - as an exercise. I personally learnt a lot in the process. Now I use EC2
for everything I do. It is a _LOT_ of fun (imho).

Interesting links: [http://jimmyg.org/2007/09/01/amazon-ec2-for-people-who-
prefe...](http://jimmyg.org/2007/09/01/amazon-ec2-for-people-who-prefer-
debian-and-python-over-fedora-and-java/) [http://jimmyg.org/2007/09/01/custom-
debian-ec2-amis-from-xen...](http://jimmyg.org/2007/09/01/custom-debian-
ec2-amis-from-xen-images/)

~~~
tx
Hm... the toy app you ported took about 5 seconds to respond. Slo-o-o-o-ow. Is
that EC2 overhead?

This is the kind of thing we were trying to avoid and ultimately (again)
decided on our own servers in a data center.

~~~
kirubakaran
It is near instantaneous for me and I am in Seattle,WA,USA. I've heard from
many sources that AWS is slow if you are outside the US. Someone even brought
this up in the AWS dev conference and the Amazon guys just dodged it and gave
a generic 'things are being improved' response.

If <http://www.instantwordsearch.com/> look up is painfully slow but
<http://www.instantwordsearch.com/backstage.html> (statically served 103KB
text) is very fast, then you can conclude that the problem is with my app.
Otherwise it might be safe to blame EC2.

~~~
tx
I am in Austin, TX and the front page took 5 seconds. I did not type anything
or clicked anywhere.

The problem with EC2 and other super-managed hosting solutions (Joyent comes
to mind) is inconsistency: I am sure they're moving VMs around, and
occasionally they end up on overloaded servers.

~~~
wmf
But I am equally sure that EC2 does not oversell CPU/RAM resources and does
not move VMs around. I don't think Xen even supports memory overcommit.

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SwellJoe
We're announcing a product that manages EC2 instances in the next week or so
(along with Solaris Zones, Xen, and vserver instances). So far we're seeing
pretty good results with the people who are using EC2, but reliability is
currently less than ideal. If EC2 were on the various hosting reliability
charts I'm pretty sure it'd be down in the bottom half of the pack (and given
some of the podunk three-server operations out there calling themselves
"hosting providers" this is pretty dismal). As far as I can tell, you can
expect several minutes of downtime every month, and sometimes longer. Most of
the top tier hosts average a couple of minutes per year downtime...but the
fluid nature of EC2 should make it possible to get near 100% uptime...when
Amazon takes a network segment down, they can theoretically do a live
migration of your instances. So far, they don't seem to actually have the
capability to do so.

The S3 piece of the equation brings it back up in usefulness...but I don't
know that I'd want to rely on it exclusively for my web applications just yet,
unless high volume storage was a core part of my problem domain.

------
piers
I've not used it, but have a read of this:
[http://www.25hoursaday.com/weblog/2007/07/04/AmazonEC2S3Does...](http://www.25hoursaday.com/weblog/2007/07/04/AmazonEC2S3DoesntCutItForRealApplications.aspx)

~~~
gojomo
That post ("Amazon EC2 + S3 Doesn't Cut it for Real Applications") contains a
false statement which the author has not corrected, even though commenters
there quickly pointed out its falsehood. The falsehood is: "There is no
persistent storage in EC2 so if your virtual server goes down for any reason
such as taking it down to install security patches or a system crash, all your
data is lost."

Instances can reboot, under operator control or due to a crash, and still
retain their existing hard drive storage. Only less frequent 'instance
termination' causes a loss of hard drive contents.

True, there are no guarantees that any instance won't be terminated by Amazon
or other system failures at any time, so you're supposed to have your own
backup and persistence strategy. But in practice, full terminations are rare,
and Amazon has even given warnings when system upgrades mean large instance
turnover is expected. (Though, there is no guarantee they will do so.)

So the falsehoods above are "[data is lost] if your virtual server goes down
for any reason" and both concrete examples given, "taking it down to install
security patches" and "system crash".

~~~
felipe
Three days ago I received an email from Amazon alerting me that "one or more
of your instances are running on hosts degraded due to hardware failure.", and
giving me a week to migrate to another instance. I have a script that creates
daily instance images as a back-up procedure, so the "migration" was just a
matter of starting another instance using the most recent image and I was up
and running.

I looked back on my logs and found out that the particular degraded instance
was running since June without any problems or shutdowns. Not bad for a VPS...

I'm very aware that Amazon provides no guarantees, but I have to say that my
confidence on EC2 increased after this incident.

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staunch
I think it's super useful for certain kinds of things where you need lots of
servers on-demand. For most startups I think boring old fashioned dedicated
server accounts are the way to go. The price, simplicity, and control is
unbeatable IMHO.

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kvogt
We run a live video cluster on EC2 that scaled from 10 nodes to 100+ and back
again several times. Amazon keeps things running smoothly even when we're
pushing close to 2gbps of video to 14,000 simultaneous clients. So I would say
it performs very well for jobs requiring lots of computation or bandwidth.

However... we have our web servers in a colo. Ping times to EC2 aren't
fantastic, so we use a traditional CDN for static content and a colo for
application servers in order to keep things snappy.

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breck
I talked to a guy last night at TC40 who swears by EC2. But he recommends
using RightScale on top of it. I've given only a cursory glance at RS, but it
looks interesting. And the guy just sold his company in the past week so it
definitely worked for him.

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davidw
First impression:

My requests time out an awful lot:

Read timeout. Please try again later. If this persists please visit the AWS
developer forums to see if it's the result of a known issue.

That and doubts about permanent storage are downers.

~~~
kirubakaran
Can you please give more details about your set up, the country you are
accessing EC2 from etc? I am curious to know coz I am in the process of
putting all my eggs in the EC2 basket now.

~~~
davidw
I'm in Austria, and I quite often ssh into servers in the US, with no problems
at all. I've been having lots of issues with the EC2 tools timing out, though.

~~~
kirubakaran
Thanks. I've heard that many non-US users have problems with EC2.

