I have a RESTful webservice running on Amazon EC2. Since my application needs to deal with large number of photos, I plan to put them on Amazon S3. So the URL for retrieving a photo from S3 could look like this:
http://johnsmith.s3.amazonaws.com/photos/puppy.jpg
Is there any way or necessity to cache the images on EC2? The pros and cons I can think of is:
1) Reduced S3 usage and cost with improved image fetching performance. However on the other hand EC2 cost can rise plus EC2 may not have the capability to handle the image cache due to bandwidth restrictions.
2) Increased development complexity cuz you need to check the cache first and ask S3 to transfer the image to EC2 and then transfer to the client.
I'm using the EC2 micro instance and feel it might be better not to do the image cache on EC2. But the scale might grow fast and eventually will need a image cache.(Am I right?) If cache is needed, is it better to do it on EC2, or on S3? (Is there a way for caching for S3?)
By the way, when the client uploads an image, should it be uploaded to EC2 or S3 directly?
Why bring EC2 into the equation? I strongly recommend using CloudFront for the scenario.
When you use CloudFront in conjunction with S3 as origin; the content gets distributed to 49 different locations worldwide ( as of count of edge locations worldwide today ) directly working out as a cache globally and the content being fetched from nearest location based on the latency to your end users.
The way you don't need to worry about the scale and performance of Cache and EC2 can straightforward offload this to CloudFront and S3.
Static vs dynamic
Generally speaking, here are the tiers:
best CDN (cloudfront)
good static hosting (S3)
okay dynamic (EC2)
Why? There are a few reasons.
maintainability and scalability: cloudfront and S3 scale "for free". You don't need to worry about capacity or bandwidth or request rate.
price: approximately speaking, it's cheaper to use S3 than EC2.
latency: CDNs are located around the world, leading to shorter load times.
Caching
No matter where you are serving your static content from, proper use of the Cache-Control header will make life better. With that header you can tell a browser how long the content is good for. If it is something that never changes, you can instruct a browser to keep it for a year. If it frequently changes, you can instruct a browser to keep it for an hour, or a minute, or revalidate every time. You can give similar instructions to a CDN.
Here's a good guide, and here are some examples:
# keep for one year
Cache-Control: max-age=2592000
# keep for a day on a CDN, but a minute on client browsers
Cache-Control: s-maxage=86400, maxage=60
You can add this to pages served from your EC2 instance (no matter if it's nginx, Tornado, Tomcat, IIS), you can add it to the headers on S3 files, and CloudFront will use these values.
I would not pull the images from S3 to EC2 and then serve them. It's wasted effort. There are only a small number of use cases where that makes sense.
Few scenarios when EC2 caching instance:
your upload/download ratio is far from 50/50
you hit S3 limit 100req/sec
you need URL masking
you want to optimise kernel, TCP/IP settings, cache SSL session for clients
you want proper cache invalidating mechanism for all geo locations
you need 100% control where data is stored
you need to count number of requests
you have custom authentication mechanism
For number of reasons I recommend to take a look at Nginx S3 proxy.
Related
I read this and understand the difference between CloudFront and S3 Transfer Acceleration. Since both can improve the download speed(though S3 Transfer Acceleration is mainly for uploading, it also improving download), can I use them together? Based on my test, it seems to be impossible as CloudFront will always take the S3 bucket URL like xxx.s3.amazonaws.com/ as the source. It cannot take xxx.s3-accelerate.amazonaws.com as the source.
Amazon CloudFront caches content in 225+ Points of Presence.
The first user who requests a piece of content in a particular location will trigger the edge location to 'pull' the content from the origin. Future requests for that content will be served from the cache. It is an excellent way to reduce latency for users spread around the world.
Amazon S3 Transfer Acceleration always makes a request back to the source bucket. This is good for uploading, but does not reduce latency for users spread around the world since all of their requests would need to go to the source bucket.
You might be able to have CloudFront in front of S3 Transfer Acceleration, but CloudFront uses the AWS network to reach origin buckets, so it is unlikely to make any difference. If you do experiment with this, let us know your findings!
Given that storing static content is the main use case for Amazon S3 service and considering the fact that many large players rely on CDN to scale distribution of such content, I want to know whether Amazon S3 provides some sort of CDN functionality? I can easily imagine them storing multiple copies of content for fault tolerance/scalability, but does that put it on par with CDNs? If not, why not?
From What Is Amazon CloudFront?:
Amazon CloudFront is a web service that speeds up distribution of your static and dynamic web content, such as .html, .css, .js, and image files, to your users. CloudFront delivers your content through a worldwide network of data centers called edge locations. When a user requests content that you're serving with CloudFront, the user is routed to the edge location that provides the lowest latency (time delay), so that content is delivered with the best possible performance.
You can decide to put Amazon CloudFront in front of your application. This will enable static content to be cached in edge locations around the world.
Background
We have developed an e-commerce application where I want to use CDN to improve the speed of the app and also to reduce the load on the host.
The application is hosted on an EC2 server and now we are going to use Cloud Front.
Questions
After reading a lot of articles and documents, I have created a distribution for my sample site. After doing all the experience I have come to know the following things. I want to be sure if am right about these points or not.
When we create a distribution it takes all the accessible data from the given origin path. We don't need to copy/ sync our files to cloud front.
We just have to change the path of our application according to this distribution CNAME (if cname is given).
There is no difference between placing the images/js/CSS files on S3 or on our own host. Cloud Front will just take them by itself.
The application will have thousands of pictures of the products, should we place them on S3 or its ok if they are on the host itself? Please share any good article to understand the difference of both the techniques.
Because if S3 is significantly better then I'll have to make a program to sync all such data on S3.
Thanks for the help.
Some reasons to store the images on Amazon S3 rather than your own host (and then serve them via Amazon CloudFront):
Less load on your servers
Even though content is cached in Amazon CloudFront, your servers will still be hit with requests for the first access of each object from every edge location (each edge location maintains its own cache), repeated every time that the object expires. (Refreshes will generate a HEAD request, and will only re-download content that has changed or been flushed from the cache.)
More durable storage
Amazon S3 keeps copies of your data across multiple Availability Zones within the same Region. You could also replicate data between your servers to improve durability but then you would need to manage the replication and pay for storage on every server.
Lower storage cost
Storing data on Amazon S3 is lower cost than storing it on Amazon EBS volumes. If you are planning on keeping your data in both locations, then obviously using S3 is more expensive but you should also consider storing it only on S3, which makes it lower cost, more durable and less for you to backup on your server.
Reasons to NOT use S3:
More moving parts -- maintaining code to move files to S3
Not as convenient as using a local file system
Having to merge log files from S3 and your own servers to gather usage information
I'm interested in hosting a website for a small business (< 100 users / month) and I wanted to try going 'serverless'. I've read that using Amazon S3, Lambda and DynamoDB is a way to set this up, by hosting the front-end on S3, using Lambda functions to access the back-end, and storing data in DynamoDB. I'll need to run a script on page load to get data to display, save user profiles/allow logins, and acccept payments using Stripe or Braintree.
Is this a good situation to use this setup, or am I better off just using EC2 with a LAMP stack? Which is better in terms of cost?
It is a perfectly good solution, and will probably cost you nothing at all to host on AWS - literally pennies a month. I host several low traffic sites this way and it works well.
The only caveat would be, since your traffic is so slow, almost every time someone hits a page, if it needs to make any back-end calls, those lambda functions will likely need a 'cold-start', which may introduce a delay and cause the page to load a bit slower than if it had more traffic that tended to keep the lambda cache 'warm'.
After reading some AWS documentations, I am wondering what's the difference between these different use cases if I want to delivery (js, css, images and api request) content in Asia (including China), US, and EU.
Store my images and static files on S3 US region and setup EU and Asia(Japan or Singapore) cross region replication to sync with US region S3.
Store my images and static files on S3 US region and setup cloudfront CDN to cache my content in different locations after initial request.
Do both above (if there is significant performance improvement).
What is the most cost effective solution if I need to achieve global deployment? And how to make request from China consistent and stable (I tried cloudfront+s3(us-west), it's fast but the performance is not consistent)?
PS. In early stage, I don't expect too many user requests, but users spread globally and I want them to have similar experience. The majority of my content are panorama images which I'd expect to load ~30MB (10 high res images) data sequentially in each visit.
Cross region replication will copy everything in a bucket in one region to a different bucket in another region. This is really only for extra backup/redundancy in case an entire AWS region goes down. It has nothing to do with performance. Note that it replicates to a different bucket, so you would need to use different URLs to access the files in each bucket.
CloudFront is a Content Delivery Network. S3 is simply a file storage service. Serving a file directly from S3 can have performance issues, which is why it is a good idea to put a CDN in front of S3. It sounds like you definitely need a CDN, and it sounds like you have tested CloudFront and are unimpressed. It also sounds like you need a CDN with a larger presence in China.
There is no reason you have to chose CloudFront as your CDN just because you are using other AWS services. You should look at other CDN services and see what their edge networks looks like. Given your requirements I would highly recommend you take a look at CloudFlare. They have quite a few edge network locations in China.
Another option might be to use a CDN that you can actually push your files to. I've used this feature in the past with MaxCDN. You would push your files to the CDN via FTP, and the files would automatically be pushed to all edge network locations and cached until you push an update. For your use case of large image downloads, this might provide a more performant caching mechanism. MaxCDN doesn't appear to have a large China presence though, and the bandwidth charges would be more expensive than CloudFlare.
If you want to serve your files in S3 buckets to all around the world, then I believe you may consider using S3 Transfer acceleration. It can be used in cases where you either upload to or download from your S3 bucket . Or you may also try AWS Global Accelerator
CloudFront's job is to cache content at hundreds of caches ("edge locations") around the world, making them more quickly accessible to users around the world. By caching content at locations close to users, users can get responses to their requests more quickly than they otherwise would.
S3 Cross-Region Replication (CRR) simply copies an S3 bucket from one region to another. This is useful for backing up data, and it also can be used to speed up content delivery for a particular region. Unlike CloudFront, CRR supports real-time updating of bucket data, which may be important in situations where data needs to be current (e.g. a website with frequently-changing content). However, it's also more of a hassle to manage than CloudFront is, and more expensive on a multi-region scale.
If you want to achieve global deployment in a cost-effective way, then CloudFront would probably be the better of the two, except in the special situation outlined in the previous paragraph.