Monitor Multiple Rails Applications - ruby-on-rails

Are there any tools that I can run on my server to monitor multiple rails applications?
I need to monitor the number of requests each application receives, how much memory each application is using, how much of the cpu is being used and other stats similar to those. I need to see the stats for each individual rails application.

I recommend you try NewRelic RPM.
The free version:
RPM Lite is the most widely used
solution for basic web application
monitoring. RPM Lite provides
application monitoring for unlimited
Java, Ruby or JRuby applications, for
unlimited users, for an unlimited
time. What a deal! With RPM Lite you
can identify overall app health, app
response time, throughput, Apdex SLA
scoring, cluster breakdown, and Notes.
You can also see where web
transactions are spending the most
time, isolate the worst offenders, and
determine where to focus your
remediation efforts
Later edit:
An alternative to NewRelic RPM is ScoutApp, that has a lot of plugins covering all your required features.
If you need something that can be run on your server, there is also the munin plugins gem that you may try. If you need a users monitoring tools (kind of like Google Analytics)m you can use the RailStat gem.

The Request Log Analyzer gem can be useful, is free, and works by analyzing Rails log files. Thus, there's no chance of it having any negative impact on your application's performance.

Related

Heroku configuration for Ruby on Rails application

I’ve set a client up with Heroku for their Ruby on Rails application and have had a great deal of trouble over the years with their application not running well regardless of how much money we spend on additional resources, find their documentation highly confusing. I’ve never been able to understand their specific terminology and documentation. We are constantly getting "H12" errors and "R14" errors etc. The memory usage and dyno loads are constantly spiking. And yet this is a small to medium-sized business without a massive amount of traffic. Wondering if anybody out there who does understand the ins and outs of Heroku can look this configuration over and tell me if it makes sense:
DB_POOL: 10
MALLOC_ARENA_MAX: 2
RAILS_MAX_THREADS: 5
WEB_CONCURRENCY: 4
Ruby 2.7
Rails 6.0
Puma
8 2x web dynos
5 1x worker dynos
$50 Postgres standard 0 database
$15 Memcachier
$10 Rediscloud
...etc addons
Your WEB_CONCURRENCY is too high for your Standard-2x dynos. The recommended default is 2: https://devcenter.heroku.com/articles/deploying-rails-applications-with-the-puma-web-server#recommended-default-puma-process-and-thread-configuration
This is likely contributing to your R14 errors as higher web concurrency means more memory usage. So you need to either lower your web concurrency (which may mean you also need to increase the # of dynos to compensate) or you need to use bigger dynos.
You already have MALLOC_ARENA_MAX=2 but not sure if you are using jemalloc. You might want to try that too.
Of course, you may also have other memory issues in your app - check out some tips here. I also recommend adding a monitoring tool like AppSignal as it's capable of tracking memory allocations per transaction.
For mitigating H12s:
Ensure you have installed something like the rack-timeout gem, which ensures that a long-running request is dropped at the dyno-level and thus avoids the H12 error (you get a Rack::TimeoutError exception instead). Set the timeout to 15s so that it is well under the 30s for H12 timeout.
Investigate your slow transactions. A monitoring tool is key here, i.e. New Relic (start with lowest-priced paid plan - free plan does not allow transaction tracing). Here is their blog post on how to trace transactions
When you've identified the problem - fix it!
if the bottleneck is external:
check for external API limits and throttling
add timeouts and make app resilient to slow external responses
if the bottleneck is due to the database:
optimize slow queries
check cache hit rates
check for the # of waiting connections and db locks -> if the number of waiting connections is consistently above 0 for X minutes, that indicates you have some long locks that you'll need to investigate. Waiting connections is easiest to track over time with Librato (free plan should do fine)
if the bottleneck is other app code:
add more custom instrumentation to get more insights, i.e. New Relic instructions
address app code issues
I want to stress the importance of monitoring tools to help diagnose issues and help determine optimal resource usage. Doing things like figuring out the correct concurrency configs, the correct size and # of dynos to run are virtually impossible without proper monitoring tools. Hopefully you have some already that are covered by your etc add-ons that are not listed, but if you do not, I'll summarize my recommendations and mention a couple other tips:
To get more metrics info, ensure you have enabled log-runtime-metrics
Also enable Ruby language metrics
Add a monitoring tool that can track Ruby memory allocations like AppSignal. Scout APM can do this too but I think their plans capable of this are more expensive (requires Scout Insights feature)
Add the lowest-paid version of New Relic. This is my go-to tool for transaction tracing. AppSignal can do this too if you don't want to pay for another tool, but I find it easier with New Relic.
Add Librato. It offers some great charts out of the box, including a set of Postgres charts in its own dashboard.
Set alerts in your monitoring apps to warn you about things like response times so you can look into them!
And of course, make all your changes in staging first AND load test them to see the impacts of your changes before attempting in production!
Update: I also just noticed that you said you are using Standard-0 Postgres, which means it has a 120 connection limit. So if you end up lowering your WEB_CONCURRENCY and increasing the # of dynos, watch out for your total connections to that database. Beyond just the fact that there is a limit, more connections also mean more overhead for your db anyway so if you are close to your connection limit, you are more likely to see db performance suffer. You may want to upgrade to another plan that has a higher connection limit or use pgbouncer as your connection pooler to avoid connection limits.

passenger 5 performance compared to unicorn/thin/puma/etc

I've been searching around for performance tests on the new passenger 5 as I read here it became way faster.
I tried to find other ressources confirming this but no luck. Has anyone tried to install it and see the difference?
Passenger 5 scores better on custom-picked benchmarks because it has a built-in caching layer ("turbocaching") that can avoid actually running your application code for identical requests in a short timeframe; it will not make your actual application code run any faster. This caching layer is only active in certain constrained situations, and is not likely to provide much benefit in the vast majority of actual cases. If you aren't careful, the caching layer may actually end up breaking your application - I demonstrated several security vulnerabilities due to the caching layer to Phusion during the 5 beta phase (which they fixed, at the cost of the caching layer not being able to cache nearly as much). IMO, the Raptor/Passenger 5 benchmarks are deceptive marketing fluff, and the caching layer exists primarily to win Hello World benchmarks, and you should probably just ignore them.
That said, the speed of your application server is almost certainly insignificant in the scope of your overall application performance. Passenger is a great platform because it's extremely user-friendly, well-documented, has an absolutely fantastic installer, and handles a lot of the annoying crap for you out of the box. You should use Passenger if you need the functionality it provides and don't want to screw around with a ton of config stuff. If it doesn't fit your use case, use something else that does.
If every last microsecond is of prime concern to you, you should measure your application's performance under various webservers and various workloads, and then pick the one that performs the best. Otherwise, use whatever you like the most and then switch once performance becomes an actual problem.
Footnote: If you do use Passenger 5, be sure to read the Turbocaching security changes article to be sure you don't accidentally make your application vulnerable to user data theft (or otherwise introduce bugs) through the turbocaching layer.
I recently migrated my app from Puma to Passenger.
I have to say that I'm really happy about this move, especially because I'm hosting it on Heroku.
Since I updated to Ruby 2.2, I had some memory issues with Puma due to Heroku memory limitation (512M).
I tried a couple of different configurations but without success.
Since I moved to Passenger, I saw the memory usage go down to almost half what I was consuming with Puma with the same number of server instances (3 in my case).
Regarding the response time, it seems to be pretty much the same as before but with those memory improvements. Although, I reduced my number of Heroku dynos to handle the same number of requests.
In conclusion, on my personal experience, Passenger helped me a lot reducing the memory used by the app but it didn't helped improving the average response time. Another good point is, regarding the Heroku pricing, it helped me a lot to reduce the cost of my hosting.
I know this post is not really exhaustive without any benchmarks etc... But I thought that maybe you could find it interesting to have a personal experience on a migration from Puma to Passenger.
Hope it helps :)
First of all, let's just be clear, when we talk about server performance, the question is about how well the server scales as usage increases. If your server has one or very few human users, for most apps, you will get the same end-user experience regardless of which server you use because the bottle-neck will be the performance of Ruby, not the app server.
For medium and large apps:
So let's talk about scaling. The more CPU power and RAM you have, the more you can scale. Most servers run out of RAM faster than CPU power. So the key is to minimize the amount of RAM used per request. Each request the server receives will be handled by a process or a thread. Processes use a lot of RAM, threads use very little RAM. So the goal is simply to have lots of threads and few processes.
Puma and Passenger Enterprise are both multi-threaded servers which will scale approximately the same. (Passenger's benchmarks claim to use 5MB less RAM per process, but this is negligible.) Passenger itself (the free version) is single threaded and will not scale as well as the paid Passenger Enterprise version or as well as Puma.
So if you want maximum performance, you're choosing between Puma and Passenger Enterprise. The question then becomes, is Passenger Enterprise worth the financial cost vs is Puma worth the technical expertise cost. The answer depends on what's in your brain(s), what's in your bank account(s), and your general opportunity cost.
Passenger Enterprise has some nice tools that hold your hand if you're not an expert system administrator. Puma also has some tools but they are not as powerful as what Passenger Enterprise provides. Puma requires system-level expertise if you want to get the same control and insights as Passenger Enterprise. (You can also use Puma without all the bells-and-whistles of Passenger Enterprise, but I want to keep this comparison "apples-to-apples").
Personally, I'm a low-level guy who loves configuring servers so I prefer to trade my time rather than my money for an awesome Ruby server. Therefore, I use Puma. If you're not interested in configuring low-level stuff (or if you're a company that realizes software licenses are cheaper than administrator-developers), you might be better off with a paid Passenger Enterprise license.
For the guy running a $5 VPS (or similar low-resource, low-traffic environment):
What I said above is more for higher-traffic apps on servers with considerable resources. You're just trying to get by with basics, so it does not really apply to you.
Think of Puma and Passenger Enterprise as jumbo jets that can move a lot of people very fast. That's way more than your little app needs. What you really need is the server equivalent to a Honda Civic. For that, you should consider either the free version of Passenger or Thin. Use free Passenger if you want easy setup and decent tools. Use thin if you want similar performance but have a willingness to engineer the server.
In this case, I see no reason to use anything but free Passenger unless you are looking for a challenge.
As others said, Passenger by itself doesn't make your app faster per se. Passenger itself has become a lot faster in version 5, but the app server is only a part of the response time. If your app is slow, then it doesn't matter how fast Passenger itself is.
Having said that, Passenger differentiates itself from other app servers by actively helping you to make your app faster. Passenger's turbocache is one way through which Passenger helps you. The article Dynamic Site as fast as a Static Generated One with Raptor demonstrates a good use case for the turbocache. Passenger also provides an optimization guide that gives you tips on how to optimize your app using Passenger settings.

Best web/app server to host multiple low hit rails/sinatra apps

I need to host a lot of simple rails/sinatra/padrino applications of different ruby versions each with 0..low hits per day. They belong to different owners and should be well isolated from each other.
When an app is hit it should respond in reasonably short time, but I expect several simultaneous visitors are hitting the same site to be a rare case.
I'm going to create separate os user for each application. Surely I'd like to put them as many per server as it's possible. Thus I need to choose the web server with the lowest memory footprint, which can run applications on behalf of different users with different ruby versions and gemsets.
I consider webrick,nginx+passenger,thin,apache+passenger. I suppose the reliability of all choices is sufficient for such a job, and while performance isn't an issue, the memory consumption is.
I found many posts regarding performance issues, but most of them discuss the performance tuning and issues. I couldn't find a comparison of web servers memory usage when idle.
Is "in process" webrick the best choice? Which one would you choose for that job?
And I couldn't figure out how to resolve subdomains to application ports with webrick. Shall I use nginx or apache for that?
I don't have much experience with hosting myself, but using Webrick for production is not a good idea I think. You can also check out mongrel which I saw used in production. In most cases though you will probably want to choose between thin and unicorn. Check out this http://cmelbye.github.com/2009/10/04/thin-vs-unicorn.html or google around. Good luck :-)
Why not use Heroku? Its free and gets you out of the hassle of server configuration and maintenance.

Why do people use Heroku when AWS is present? What distinguishes Heroku from AWS? [closed]

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I'm a beginner RoR programmer who's planning to deploy my app using Heroku. Word from my other advisor friends says that Heroku is really easy, good to use. The only problem is that I still have no idea what Heroku does...
I've looked at their website and in a nutshell, what Heroku does is help with scaling but... why does that even matter? How does Heroku help with:
Speed - My research implied that deploying AWS on the US East Coast would be the fastest if I am targeting a US/Asia-based audience.
Security - How secure are they?
Scaling - How does it actually work?
Cost efficiency - There's something like a dyno that makes it easy to scale.
How do they fare against their competitors? For example, Engine Yard and bluebox?
Please use layman English terms to explain... I'm a beginner programmer.
First things first, AWS and Heroku are different things. AWS offer Infrastructure as a Service (IaaS) whereas Heroku offer a Platform as a Service (PaaS).
What's the difference? Very approximately, IaaS gives you components you need in order to build things on top of it; PaaS gives you an environment where you just push code and some basic configuration and get a running application. IaaS can give you more power and flexibility, at the cost of having to build and maintain more yourself.
To get your code running on AWS and looking a bit like a Heroku deployment, you'll want some EC2 instances - you'll want a load balancer / caching layer installed on them (e.g. Varnish), you'll want instances running something like Passenger and nginx to serve your code, you'll want to deploy and configure a clustered database instance of something like PostgreSQL. You'll want a deployment system with something like Capistrano, and something doing log aggregation.
That's not an insignificant amount of work to set up and maintain. With Heroku, the effort required to get to that sort of stage is maybe a few lines of application code and a git push.
So you're this far, and you want to scale up. Great. You're using Puppet for your EC2 deployment, right? So now you configure your Capistrano files to spin up/down instances as needed; you re-jig your Puppet config so Varnish is aware of web-worker instances and will automatically pool between them. Or you heroku scale web:+5.
Hopefully that gives you an idea of the comparison between the two. Now to address your specific points:
Speed
Currently Heroku only runs on AWS instances in us-east and eu-west. For you, this sounds like what you want anyway. For others, it's potentially more of a consideration.
Security
I've seen a lot of internally-maintained production servers that are way behind on security updates, or just generally poorly put together. With Heroku, you have someone else managing that sort of thing, which is either a blessing or a curse depending on how you look at it!
When you deploy, you're effectively handing your code straight over to Heroku. This may be an issue for you. Their article on Dyno Isolation details their isolation technologies (it seems as though multiple dynos are run on individual EC2 instances). Several colleagues have expressed issues with these technologies and the strength of their isolation; I am alas not in a position of enough knowledge / experience to really comment, but my current Heroku deployments consider that "good enough". It may be an issue for you, I don't know.
Scaling
I touched on how one might implement this in my IaaS vs PaaS comparison above. Approximately, your application has a Procfile, which has lines of the form dyno_type: command_to_run, so for example (cribbed from Heroku Architecture - The Process Model):
web: bundle exec rails server
worker: bundle exec rake jobs:work
This, with a:
heroku scale web:2 worker:10
will result in you having 2 web dynos and 10 worker dynos running. Nice, simple, easy. Note that web is a special dyno type, which has access to the outside world, and is behind their nice web traffic multiplexer (probably some sort of Varnish / nginx combination) that will route traffic accordingly. Your workers probably interact with a message queue for similar routing, from which they'll get the location via a URL in the environment.
Cost Efficiency
Lots of people have lots of different opinions about this. Currently it's $0.05/hr for a dyno hour, compared to $0.025/hr for an AWS micro instance or $0.09/hr for an AWS small instance.
Heroku's dyno documentation says you have about 512MB of RAM, so it's probably not too unreasonable to consider a dyno as a bit like an EC2 micro instance. Is it worth double the price? How much do you value your time? The amount of time and effort required to build on top of an IaaS offering to get it to this standard is definitely not cheap. I can't really answer this question for you, but don't underestimate the 'hidden costs' of setup and maintenance.
(A bit of an aside, but if I connect to a dyno from here (heroku run bash), a cursory look shows 4 cores in /proc/cpuinfo and 36GB of RAM - this leads me to believe that I'm on a "High-Memory Double Extra Large Instance". The Heroku dyno documentation says each dyno receives 512MB of RAM, so I'm potentially sharing with up to 71 other dynos. (I don't have enough data about the homogeny of Heroku's AWS instances, so your milage may vary))
How do they fare against their competitors?
This, I'm afraid I can't really help you with. The only competitor I've ever really looked at was Google App Engine - at the time I was looking to deploy Java applications, and the amount of restrictions on usable frameworks and technologies was incredibly off-putting. This is more than "just a Java thing" - the amount of general restrictions and necessary considerations (the FAQ hints at several) seemed less than convenient. In contrast, deploying to Heroku has been a dream.
Conclusion
Please comment if there are gaps / other areas you'd like addressed. I feel I should offer my personal position. I love Heroku for "quick deployments". When I'm starting an application, and I want some cheap hosting (the Heroku free tier is awesome - essentially if you only need one web dyno and 5MB of PostgreSQL, it's free to host an application), Heroku is my go-to position. For "Serious Production Deployment" with several paying customers, with a service-level-agreement, with dedicated time to spend on ops, et cetera, I can't quite bring myself to offload that much control to Heroku, and then either AWS or our own servers have been the hosting platform of choice.
Ultimately, it's about what works best for you. You say you're "a beginner programmer" - it might just be that using Heroku will let you focus on writing Ruby, and not have to spend time getting all the other infrastructure around your code built up. I'd definitely give it a try.
Note, AWS does actually have a PaaS offering, Elastic Beanstalk, that supports Ruby, Node.js, PHP, Python, .NET and Java. I think generally most people, when they see "AWS", jump to things like EC2 and S3 and EBS, which are definitely IaaS offerings
AWS / Heroku are both free for small hobby projects (to start with).
If you want to start an app right away, without much customization of the architecture, then choose Heroku.
If you want to focus on the architecture and to be able to use different web servers, then choose AWS. AWS is more time-consuming based on what service/product you choose, but can be worth it. AWS also comes with many plugin services and products.
Heroku
Platform as a Service (PAAS)
Good documentation
Has built-in tools and architecture.
Limited control over architecture while designing the app.
Deployment is taken care of (automatic via GitHub or manual via git commands or CLI).
Not time consuming.
AWS
Infrastructure as a Service (IAAS)
Versatile - has many products such as EC2, LAMBDA, EMR, etc.
Can use a Dedicated instance for more control over the architecture, such as choosing the OS, software version, etc. There is more than one backend layer.
Elastic Beanstalk is a feature similar to Heroku's PAAS.
Can use the automated deployment, or roll your own.
As Kristian Glass Said, there is no comparison between IaaS(AWS) and PaaS(Heroku, EngineYard).
PaaS basically helps developers to speed the development of app,thereby saving money and most importantly innovating their applications and business instead of setting up configurations and managing things like servers and databases. Other features buying to use PaaS is the application deployment process such as agility, High Availability, Monitoring, Scale / Descale, limited need for expertise, easy deployment, and reduced cost and development time.
But still there is a dark side to PaaS which lead barrier to PaaS adoption :
Less Control over Server and databases
Costs will be very high if not governed properly
Premature and dubious in current day and age
Apart from above you should have enough skill set to mange you IaaS:
Hardware acquisition
Operating System
Server Software
Server Side Scripting Environment
Web server
Database Management System(Mysql, Redis etc)
Configure production server
Tool for testing and deployment
Monitoring App
High Availability
Load Blancing/ Http Routing
Service Backup Policies
Team Collaboration
Rebuild Production
If you have small scale business, PaaS will be best option for you:
Pay as you Go
Low start up cost
Leave the plumbing to expert
PaaS handles auto scaling/descaling, Load balancing, disaster recovery
PaaS manages all security requirements
PaaS manages reliability, High Availability
Paas manages many third party add-ons for you
It will be totally individual choice based on requirement. You can have details on my PPT Hosting Rails Apps.
There are a lot of different ways to look at this decision from development, IT, and business objectives, so don't feel bad if it seems overwhelming. But also - don't overthink scalability.
Think about your requirements.
I've engineered websites which have serviced over 8M uniques a day and delivered terabytes of video a week built on infrastructures starting at $250k in capital hardware unr by a huge $MM IT labor staff.
But I've also had smaller websites which were designed to generate $10-$20k per year, didn't have very high traffic, db or processing requirements, and I ran those off a $10/mo generic hosting account without compromise.
In the future, deployment will look more like Heroku than AWS, just because of progress. There is zero value in the IT knob-turning of scaling internet infrastructures which isn't increasingly automatable, and none of it has anything to do with the value of the product or service you are offering.
Also, keep in mind with a commercial website - scalability is what we often call a 'good problem to have' - although scalability issues with sites like Facebook and Twitter were very high-profile, they had zero negative effect on their success - the news might have even contributed to more signups (all press is good press).
If you have a service which is generating a 100k+ uniques a day and having scaling issues, I'd be glad to take it off your hands for you no matter what the language, db, platform, or infrastructure you are running on!
Scalability is a fixable implementation problem - not having customers is an existential issue.
Actually you can use both - you can develop an app with amazon servers ec2. Then push it (with git) to heroku for free for awhile (use heroku free tier to serve it to the public) and test it like so. It is very cost effective in comparison to rent a server, but you will have to talk with a more restrictive heroku api which is something you should think about. Source: this method was adopted for one of my online classes "Startup engineering from Coursera/Stanford by Balaji S. Srinivasan and Vijay S. Pande
Well, people usually ask this question: Heroku or AWS when starting to deploy something.
My experiment of using both of Heroku & AWS, here is my quick review and comparison:
Heroku
One command to deploy whatever your project types: Ruby on Rails, Nodejs
So many 1-click to integrate plugins & third parties: It is super easy to start with something.
Don't have auto-scaling; that means you need to scale up/down manually
Cost is expensive, especially, when system needs more resources
Free instance available
The free instance goes to sleep if it is inactive.
Data center: US & EU only
CAN dive into/access to machine level by using Heroku run bash (Thanks, MJafar Mash for the advice) but it is kind of limited! You don't have full access!
Don't need to know too much about DevOps
AWS - EC2
This just like a machine with pre-config OS (or not), so you need to install software, library to make your website/service go online.
Plugin & Library need to be integrated manually, or automation script (public script & written by you)
Auto scaling & load balancer are the supported services, just learn how to config & integrate to your system
Cost is quite cheap, depends on which services and number of hours you use it
There are several free hours for T2.micro instances, but usually, you will pay few dollars every month (if still using T2.micro)
Your free instance won't go to sleep, available 24/7 (because you may pay for it :) )
Data center: around the world. Pick the region which is the best fit for you.
Dive into machine level. So you can enjoy it
Some knowledge about DevOps, but it is okay, Stackoverflow is helpful there!
AWS Elastic Beanstalk an alternative of Heroku, but cheaper
Elastic Beanstalk was announced as a public beta from 2010; it helps we easier to work with deployment. For detail please go here
Beanstalk is free, the cost you will pay will be for the services you use & number of hours of usage.
I use Elastic Beanstalk for a long time, and I think it can be the replacement of Heroku and cheaper!
Summary
Heroku: Easy at beginning, FREE instance, but expensive later
AWS: Not easy, free hours available, kind of cheaper, Beanstalk should be concerned to use
So in my current system, I use Heroku for staging and Beanstalk for production!
The existing answers are broadly accurate:
Heroku is very easy to use and deploy to, can be easily configured for auto-deployment a repository (eg GitHub), has lots of third party add-ons and charges more per instance.
AWS has a wider range of competitively priced first party services including DNS, load balancing, cheap file storage and has enterprise features like being able to define security policies.
For the tl;dr skip to the end of this post.
AWS ElasticBeanstalk is an attempt to provide a Heroku-like autoscaling and easy deployment platform. As it uses EC2 instances (which it creates automatically) EB servers can do everything any other EC2 instance can do and it's cheap to run.
Deployment with EB is very slow; deploying an update can take 10-15 minutes per server and deploying to a larger cluster can take the best part of an hour - compared to just seconds to deploy an update on Heroku. Deployments on EB are not handled particularly seamlessly either, which may impose constraints on application design.
You can use all the services ElasticBeanstalk uses behind the scenes to build your own bespoke system (with CodeDeploy, Elastic Load Balancer, Auto Scaling Groups - and CodeCommit, CodeBuild and CodePipeline if you want to go all in) but you can definitely spend a good couple of weeks setting it up the the first time as it's fairly convoluted and slightly tricker than just configuring things in EC2.
AWS Lightsail offers a competitively priced hosting option, but doesn't help with deployment or scaling - it's really just a wrapper for their EC2 offering (but costs much more). It lets you automatically run a bash script on initial setup, which is nice touch but it's pricy compared to the cost of just setting up an EC2 instance (which you can also do programmatically).
Some thoughts on comparing (to try and answer the questions, albeit in a roundabout way):
Don't underestimate how much work system administration is, including keeping everything you have installed up to date with security patches (and occasional OS updates).
Don't underestimate how much of a benefit automatic deployment, auto-scaling, and SSL provisioning and configuration are.
Automatic deployment when you update your Git repository is effortless with Heroku. It is near instant, graceful so there are no outages for end users and can be set to update only if the tests / Continuous Integration passes so you don't break your site if you deploy broken code.
You can also use ElasticBeanstalk for automatic deployment, but be prepared to spend a week setting that up the first time - you may have to change how you deploy and build assets (like CSS and JS) to work with how ElasticBeanstalk handles deployments or build logic into your app to handle deployments.
Be aware in estimating costs that for seamless deployment with no outage on EB you need to run multiple instances - EB rolls out updates to each server individually so that your service is not degraded - where as Heroku spins up a new dyno for you and just deprecates the old service until all the requests to it are done being handled (then it deletes it).
Interestingly, the hosting cost of running multiple servers with EB can be cheaper than a single Heroku instance, especially once you include the cost of add-ons.
Some other issues not specifically asked about, but raised by other answers:
Using a different provider for production and development is a bad idea.
I am cringing that people are suggesting this. While ideally code should run just fine on any reasonable platform so it's as portable as possible, versions of software on each host will vary greatly and just because code runs in staging doesn't mean it will run in production (e.g. major Node.js/Ruby/Python/PHP/Perl versions can differ in ways that make code incompatible, often in silent ways that might not be caught even if you have decent test coverage).
What is a good idea is to leverage something like Heroku for prototyping, smaller projects and microsites - so you can build and deploy things quickly without investing a lot of time in configuration and maintenance.
Be sure to factor in the cost of running both production and pre-production instances when making that decision, not forgetting the cost of replicating the entire environment (including third party services such as data stores / add ons, installing and configuring SSL, etc).
If using AWS, be wary of AWS pre-configured instances from vendors like Bitnami - they are a security nightmare. They can expose lots of notoriously vulnerable applications by default without mentioning it in the description.
Consider instead just using a well supported mainstream distribution, such as Ubuntu or Debian (or CentOS if you need RPM support).
Note: Amazon offer have their own distribution called Amazon Linux, which uses RPM, but it's EC2 specific and less well supported by third party/open source software.
You could also setup an EC2 instance on AWS (or Lightsail) and configure with something like flynn or dokku on it - on which you could then deploy multiple sites easily, which can be worth it if you maintain a lot of services or want to be able to spin up new things easily. However getting it set up is not as automagic as just using Heroku and you can end up spending a lot of time configuring and maintaining it (to the point I've found deploying using Amazon clustering and Docker Swarm to be easier than setting them up; YMMV).
I have used AWS EC instances (alone and in clusters), Elastic Beanstalk and Lightsail and Heroku at the same time depending on the needs of the project I'm working on.
I hate spending time configuring services but my Heroku bill would be thousands per year if I used it for everything and AWS works out a fraction of the cost.
tl;dr
If money was never an issue I'd use Heroku for almost everything as it's a huge timesaver - but I'd still want to use AWS for more complicated projects where I need the flexibility and more advanced services that Heroku doesn't offer.
The ideal scenario for me would be if ElasticBeanstalk just worked more like Heroku - i.e. with easier configuration and quicker and a better deployment mechanism.
An example of a service that is almost this is now.sh, which actually uses AWS behind the scenes, but makes deployments and clustering as easy as it is on Heroku (with automatic SSL, DNS, graceful deployments, super-easy cluster setup and management).
I've used it quite lot for both Node.js app and Docker image deployments, the major caveat is the instances are shared (something reflected in their lower cost) and currently no option to buy dedicated instances. However their open source deployment tool 'now' can also be used to deploy to dedicated instances on AWS as well as Google Cloud and Azure.
It's been a significant percentage of our business migrating people from Heroku to AWS. There are advantages to both, but it's gets messy on Heroku after a while... once you need a certain level of complexity no longer easy to maintain with Heroku's limitations.
That said, there are increasingly options to have the ease of Heroku and the flexibility of AWS by being on AWS with great frameworks/tools.
Funny thing is Heroku actually uses AWS on the backend. It takes away all the overhead and does architecture management on EC2 for you. (Got that knowledge from a senior engineer at a Big Company during an Interview)
Sometimes, I wonder why people compare AWS to Heroku. AWS is an IAAS( infrastructure as a service) it clearly speaks how robust and calculative the system is. Heroku, on the other hand, is just a SAAS, it is basically just one fraction of AWS services. So why struggle with setting up AWS when you can ship your first product to the prime using Heroku.
Heroku is free, simple and easy to deploy almost all types of stacks to the web. Heroku is specifically built to bypass all the hassles of shipping your application to a live server in less than no time.
Nevertheless, you may want to deploy your application using any of the tutorials from both parties and compare
AWS DOCS and Heroku Docs
Well Heroku uses AWS in background, it all depends on the type of solution you need. If you are a core linux and devops guy you are not worried about creating vm from scratch like selecting ami choosing palcement options etc, you can go with AWS. If you want to do things on surface level without having those nettigrities you can go with heroku.
Even though both AWS and Heroku are cloud platforms, they are different as AWS is IaaS and Heroku is PaaS
Well! I observer Heroku is famous in budding and newly born developers while AWS has advanced developer persona. DigitalOcean is also a major player in this ground. Cloudways has made it much easy to create Lamp stack in a click on DigitalOcean and AWS. Having all services and packages updates in a click is far better than doing all thing manually.
You can check out completely here: How to Host PHP on Amazon AWS EC2
Amazon Web Services (AWS) offers lots of services from IaaS to PaaS with assured 99.9999999% durability and availability of data and infrastructure. AWS offers infrastructure automation along with several tools for developers to pipeline their application deployment process.
On the other hand, Heroku is just PaaS which offers services to manage your platform on their cloud. It nowhere stands with AWS whether it is infrastructure or security.
Heroku is like subset of AWS. It is just platform as a service, while AWS can be implemented as anything and at any level.
The implementation depends on what the business requirement. If it fits in either, use accordingly.

Rails response time and server health monitoring tools

I have a Rails 3 application running in production. What are the tools available in the market to monitor response time and server health.
I am aware of New Relic but response time monitoring is available only in gold version which is $200/month.
For monitoring the health of the system I know of Server Density.
Any other tool?
I have been using ServerDensity for one year and I'm extremely satisfied. Recently a GitHub user released a Passenger plugin for ServerDensity.
If you want something more Ruby-oriented, have a look at Scout.
The Request Log Analyzer gem can be useful, is free, and works by analyzing Rails log files. Thus, there's no chance of it having any negative impact on your application's performance.

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