Our website is getting slow and we are in need of an upgrade.
We are currently AWS and have 1 micro ec2 instance that proved effective while our website had less traffic. Now when we get more traffic, our site is getting slower.
We can't seem to settle an argument.
Which would be better:
Adding multiple additional micro/small instances and have them managed either by nginx or amazon cloud computing
OR
Upgrading our micro instance into a large/xlarge instance.
which would be more effective considering the tasks to be performed by the server are simple, and considering the total amount of ram and processing power is similar. 1 big, or many small?
Thanks
Tough to say -
Option #2 is going to be the easiest to do, turn your server off, resize it, turn it back on get more capacity just by paying more money. Easy to do, but maybe not the best long-term solution. What will you do when traffic continues to increase (either constantly or at certain times) and there are no more gains to be had simply by picking a bigger box?
Option #1 is going to be more work, but ultimately maybe a better strategy.
First of all, you didn't say if you have a constant need for more throughput, or if it is certain times of the day/week/month/year when the capacity is needed - if that is the case, multiple EC2 instances with auto-scale groups setup to respond to increases and decreases in demand by turning on additional instances as needed and then turning them off as demand decreases is a cost-effective option.
In addition, having multiple instances running - preferable in different availability zones, gives you fault-tolerance - when your big instance in #1 goes down, your website is down - if you have many small instances running across 2 or 3 availability zones, you can continue to function if one or more or your instances goes down, and even if AWS availability zone goes offline (rare, but it happens).
Besides the options above, without knowing anything about your application - other things you can do - move some static assets to S3 and/or use AWS cloudfront (or other CDN) to offload some of the work - this is often a cheap and easy way to get more out of an existing box.
Related
I have a multi-day analysis problem that I am running on a 72 cpu c5n EC2 instance. To get spot pricing, I made my code interruption-resilient and am launching a spot request of one instance. It works great, but this seems like overkill given that Spot can handle thousands of instances. Is this the correct way to solve my problem or am I using a sledgehammer to squash a fly?
I've tried normal EC2 launching, which works great, except that it is four times the price. I don't know of any other way to approach this except for these two ways. I thought about Fargate or containers or something, but I am running a 72 cpu c5n node, and those other options won't let me use that kind of horsepower (that I know of, hence my question).
Thanks!
Amazon EC2 Spot Instances are an excellent way to get cheaper compute (up to 90% discount). The only downside is that the instances might be stopped/terminated (your choice) if there is insufficient capacity.
Some strategies to improve your chance of obtaining spot instances:
Use instances across different Instance Types and Availability Zones because they each have different availability pools (EC2 Spot Fleet can assist with this)
Use resources on weekends and in evenings (even in different regions!) because these tend to be times of lower usage
Use Spot Instances with a specified duration (also known as Spot blocks), but this is at a higher price and a maximum duration of 6 hours
If your software permits it, you could split your load between multiple instances to get the job done faster and to be more resilient against any stoppages of your Spot instances.
Hopefully your application is taking advantage of all the CPUs, otherwise you'd be better-off with smaller instances.
what will be the best option to choose b/w less number of large instances or more number of the small instance when the performance is concerned, as the cloudwatch (load balancing and scaling) will be used if the traffic floods on the servers.
AWS is all about ELASTICITY
There is no need to provision large instances when not needed and burn out money.
There can be many instances when your CPU on one goes high and the next large instance you created remains under-utilized.
You should have medium instances to small w.r.t the tier you require (Memory Intensive, CPU, or Network) and scale those instances with properly written policies.
As long as the userdata, ami is stable you can spawn many instances within minutes making sure you are not spending way too much and saving every Penny.
SCALE WHEN NEEDED HORIZONTALLY
This is heavily dependent on your application.
I agree with Faisal Nizam's intuition of favoring horizontal scaling. However, there are many applications that will not run very well on small instances.
For example, Elastic recommends to have Elasticsearch cluster nodes with 64GB of RAM. Similar reasoning can be applied to many other data related applications, where it can be beneficial if a single instance is able to keep large data chunks in memory.
I would recommend to find the ideal instance size for your application, and from there scale horizontally.
Each EC2 has also some overhead, so you need to find a balance between large & costly instances vs. a lot and small instances with overhead.
(As of today) To vertically scale up/scale down an EC2 server, it needs to be shut down and spun back up - something to keep in mind before deciding to go for it.
I'm trying to determine if it makes sense to switch our hosting to EC2 from a dedicated dreamhost server, and if so, what EC2 instance type I should choose to get a good idea of the cost prior to switching. I would like to go low and then bump up if need be.
Current Usage:
dedicated server with 4 GB RAM and 4 CPUs
average disk usage: 783 MB
average bandwidth: 8.5 GB
This is really all the info I get from our dreamhost control panel, so hopefully it's enough to provide some recommendations on where to start.
Using the calculator located here, I'm leaning towards a t2.xlarge. Is that too much? not enough?
It is not possible for anyone to recommend the 'correct' instance type. This is because it depends on the operation of your particular application. It might be CPU-intensive, RAM-intensive, network-heavy, highly parallel, etc.
Some applications might need to handle occasional spikes of traffic, whereas other applications might be relatively consistent in their load.
The correct way to determine your 'best' instance type is to run tests that simulate the expected application load. If you can create an automated test, then you could run it against many different instance types and compare the performance vs cost.
Also, many applications are designed to be able to run across multiple instances, so it would be better to test various quantities of servers as well as their instance type.
You might also consider using Amazon EC2 Auto Scaling, which gives the ability to automatically add/remove servers based upon workload. This means that you could use much more powerful instances, but automatically turn some of them off during less-used periods. This affects the cost calculation because the more-powerful instances are more expensive, but you won't be using them all the time.
Then, you could also consider using Amazon EC2 Spot Instances, which can be up to 90% less cost but might be terminated when the demand for such instances is higher. You can also combine On-Demand and Spot Instances to give additional capacity at a lower cost.
(Spot and Auto Scaling are only really applicable if you are using more than one instance to host your application.)
And finally, if your application only requires one instance, you could also consider using Amazon Lightsail that combines the price for instance type and network bandwidth to make the price more predictable.
Bottom line: It depends!
One final word: Most companies consider switching to AWS not purely on a cost basis ("if it makes sense to switch our hosting to EC2 from a dedicated dreamhost server"), but rather on the breadth of features that AWS offers that are not available in a traditional server hosting service. If all you need is "a server", it's probably easiest to consider Amazon LightSail or keep whatever is currently working for you. The cost saving with AWS won't be dramatic (or it might not even be cheaper!), but it will offer you a lot more capabilities if you ever grow beyond just requiring "a server".
Currently i'm building a chat application base on NodeJs
So i considered choose which is the best instance type for our server?
Because AWS have a lot of choice: General purpose, compute optimize, memory optimize ....
Could you please give me advise :(
You can read this - https://aws.amazon.com/blogs/aws/choosing-the-right-ec2-instance-type-for-your-application/
Actually it doesn't matter what hosting you chose -AWS, MS Azure, Google Compute Engine etc...
If you want to get as much as you can from your servers and infrastructure, you need to solve your current task.
First of all decide how many active users at the same time you will get in closest 3-6 months.
If there will be less than 1000k active users (connections) per second - I think you can start from the smallest instance type. You should check how you can increase CPU/RAM/HDD(or SSD) of your instance.
SO when you get more users you will have a plan how to speed up your server.
And keep an eye on your server analytics - CPU/RAM/IO utilizations when you are getting more and more users.
The other questions if you need to pass some certifications related to security restrictions...
Since you are not quite sure where to start with, I would recommend to start with General Purpose EC2 instance for production from M category (M3 or M4). You can start with smaller instance type like m3.medium.
Note: If its an internal chat application with low traffic you can even consider T series EC2 instances.
The important part here is not to try to predict the capacity needs. Instead you can start small with general purpose EC2 instance and down the line looking at the resource consumption of EC2 instance you can do a proper capacity planning. Since you can both Scale the instances Horizontally and Vertically, it will require to trade of the instance type also considering Cost and timely load requirements before selecting the scaling unit of EC2 instance.
One of the approach I'm following is as follows
Start with General Purpose Instance (Unless I'm confident that there are special needs such as Networking, IO & etc.)
Do a load test(Without Autoscaling for a single EC2 instance) of the application by changing the number of users and find out the limits (How many users can a single EC2 instance can handle).
After analyzing the Memory, CPU & IO utilization, you can also consider shifting to a different EC2 category or stick with the same type. (Lets say CPU goes to its limit but memory is hardly used, you can consider using C series instances).
Scale the EC2 instance vertically by moving to the next size (e.g m3.medium to m3.large) and carry out the load tests to find out its limits.
After repeating step, 3 and 4 you can find an optimal balance between Cost and Performance.
Lets take 3 instance types with cost as X for the lowest selected (Since increasing the EC2 size in one unit, makes the cost doubles)
m3.medium - can serve 100 users, cost X
m3.large - can serve 220 users, cost 2X
m3.xlarge - can serve 300 users. cost 3X
Its an easy choice to select m3.large as the EC2 instance size since it can serve 110 per X cost.
However its not straight forward for some applications where you need to decide the instance type based on your average expected load.
Setup autoscaling and load balancing to horizontally scale the EC2 instances to handle load above average.
For more details, refer the Architecting for the Cloud: Best Practices whitepaper.
I would recommend starting with a T2.micro Linux instance. Watch the CPU usage in CloudWatch. Once the CPU usage starts to exceed 50% to 75%, or free memory gets low, or disk I/O gets saturated, switch to the next larger instance.
T2.micro Linux instances are (for the most part) free. Read the fine print. T2.micro instances are burstable which means that you can get good performance from a small instance.
Unless your chat application has a huge customer / transaction base, you (probably) won't need the other instance types.
I have a site that I will be launching soon. Not entirely sure how heavy the traffic will get.
I am using Django+Nginx+Gunicorn+Mysql. There will be support for SSL/HTTPS.
As a starting point, I am thinking of having two micro instances balanced by Elastic Load Balancing.
The MySql database will be on one of the instances. If traffic gets heavy, I might move static files to a CDN. The micro instances serve as front-end servers responsible for only churning out HTML/JSON and serving static files. Static files are mainly CSS/js and several images (not many). I foresee database will be read-heavy and less writes.
Questions:
Assuming the traffic rises to 100k page views per day, will the 2 micro instances suffice?
Do I have to move the database to a separate instance? And what instance type would be good?
What if the traffic is only 1k page views per day?
How many gunicorn processes to run on a micro instance?
In general, what type of metrics will help me determine what kind and how many instances I would need? What is the methodology to decide what kind of architecture I would need?
Thanks a lot!
Completely dependant on how dynamic the site is planning to be. Do users generate content towards the service or is it mostly static? If the former you're going to get a lot from putting stuff like avatars, images etc. into S3 and putting that on Cloudfront. Same with your static files... keeping your servers stateless will allow you scale with ease.
At 100k page views a day you will definitely struggle with just micros... you really should only use those in a development environment and aren't meant to handle stuff like serving users. I'd use at a minimum a single small instance in-front of a Load Balancer, may sound strange but you will be able to throw in another instance when things get busy without having to mess with Route 53 or potentially having your site fail. The stateless stuff is quite important now as user-generated assets may only be reference able from one instance and not the other.
At 1k page views I'd still use a small for web serving and another small for MySQL. You can look into RDS which is great if you're doing this solo, forget about needing to upgrade versions and stuff like maintenance, backups etc.
You will also be able to one-click spin up read replicas for peak. Look into the Amazon CLI as well to help automate those tasks. Cronjobs will make it a cinch if you're time stressed otherwise Opsworks, Cloudformation and Auto-Scaling will all help with the above.
Oh and just as a comparison, an Application server of mine running Apache, PHP with APC to serve our users starts to struggle with about 80 concurrent users. Runs on a small EC2 Instance with a Small RDS (which sits at about 15% at the same time as the Application Server is going downhill)
Probably not. Micro instances are not designed for heavy production loads. They use a burstable CPU profile. They can run at 2 ECU for a couple of minutes, and then they get locked at 0.1-0.2 ECU. I tend to like c1.medium, but small may be enough for you.
Maybe, as long as they are spread out during the day and not all in a short window.
1-2 per core. Micro only has 1 core.
Every application is different. The best thing to do is run your own benchmarks using tools like ab (Apache Bench)
Following the AWS best practices architecture diagram is always a good start.
http://media.amazonwebservices.com/architecturecenter/AWS_ac_ra_web_01.pdf
I strongly advise you to store all your files on Amazon S3, and use a Route 53 DNS (or any other DNS if you want) in front of it to distribute the files, because later on if you decide to use CloudFront CDN it will be very easy to change. And, just to mention using CloudFront as CDN will increase your cost only a little bit, not a huge thing.
Doesn't matter the scenario, if we're talking a about production, you should definitely go for separate instances, at least 1 EC2 for web and 1 EC2/RDS for database.
If you are geek and like to get into the nitty gritty details, create your own infrastructure and feel free to use any automation tool (puppet, chef) or not. Or if you just want to collect the profit, or have scarce resources to take care of everything, you should try Elastic Beanstalk (http://docs.aws.amazon.com/elasticbeanstalk/latest/dg/create_deploy_Python_django.html)
Anyway, going to create your own infrastructure or choose elastic beanstalk, always execute stress tests to have a better overview of your capacity planning needs. After you choose your initial environment, stress it using apache bench, siege or whatever other tool you may like.
Hope this helps.
I would suggest to use small instances instead of micro as micro instances often stop responding on heavy load and then it requires a stop-start. Use s3 for static files which helps in faster loading and have a look over cloud front.
The region for instance also helps in serving requests and if you target any specific region, create the instance selecting that region.
Create the database in new instance and attach ebs volume to that instance. Automate backup script to copy database files and store in ebs to avoid any issues. The instance selected here can be iops for faster processing over standard. Aws services provide lot of flexibility but you need to have scripts running to scale up and down the servers as per the timings.
Spot instance can help in future as they come cheap in case you are scaling up.