1 00:00:00,000 --> 00:00:02,280 So, let's talk about DynamoDB-DAX 2 00:00:02,280 --> 00:00:04,935 and DAX stands for accelerator. 3 00:00:04,935 --> 00:00:06,926 And so, accelerator means that it's a seamless cache 4 00:00:06,926 --> 00:00:08,854 for DynamoDB and you can enable it 5 00:00:08,854 --> 00:00:10,916 and you don't need to re-write any of your applications. 6 00:00:10,916 --> 00:00:12,246 They work just the same. 7 00:00:12,246 --> 00:00:14,620 But now, all the writes you do to DynamoDB, 8 00:00:14,620 --> 00:00:16,112 they go through DAX. 9 00:00:16,112 --> 00:00:19,864 And DAX basically provides you micro-second latency, 10 00:00:19,864 --> 00:00:22,030 so very low latency in case you have 11 00:00:22,030 --> 00:00:24,292 a cache read or cache query. 12 00:00:24,292 --> 00:00:26,838 So, this is a cache for your reads, 13 00:00:26,838 --> 00:00:28,624 and it solves the Hot Key problems. 14 00:00:28,624 --> 00:00:30,276 So, for example, you have a popular ad 15 00:00:30,276 --> 00:00:32,182 entering a big sale during the year, 16 00:00:32,182 --> 00:00:34,690 and that item is being queried a lot, 17 00:00:34,690 --> 00:00:36,570 so you get too many reads on that item 18 00:00:36,570 --> 00:00:38,028 and you get a Hot Key problem because 19 00:00:38,028 --> 00:00:39,358 you exceed your throughput, 20 00:00:39,358 --> 00:00:41,534 then you put DAX in front of your, 21 00:00:41,534 --> 00:00:43,531 DynamoDB cluster, and all of a sudden 22 00:00:43,531 --> 00:00:45,382 the reads are done from the cache, 23 00:00:45,382 --> 00:00:47,576 and so the problem of the Hot Key is solved. 24 00:00:47,576 --> 00:00:49,676 By default, your items live for 25 00:00:49,676 --> 00:00:51,435 five minutes in your cache. 26 00:00:51,435 --> 00:00:52,972 And you can have up to 10 nodes 27 00:00:52,972 --> 00:00:55,832 in your cache cluster, so you can scale a lot. 28 00:00:55,832 --> 00:00:58,644 It is multi AZ, so you can enable 29 00:00:58,644 --> 00:01:00,772 multiple nodes in multiple availability zones, 30 00:01:00,772 --> 00:01:02,804 and in production it's recommended you have 31 00:01:02,804 --> 00:01:06,374 a minimum of three nodes to enhance that availability. 32 00:01:06,374 --> 00:01:08,155 Finally, just like everything we've seen 33 00:01:08,155 --> 00:01:10,414 DAX is secure, you get encryption at rest 34 00:01:10,414 --> 00:01:13,211 using KMS, you have VPC end points, 35 00:01:13,211 --> 00:01:16,457 you have IAM permissions, and you can use CloudTrail. 36 00:01:16,457 --> 00:01:18,890 So here is your DynamoDB, and you have say, 37 00:01:18,890 --> 00:01:20,811 three tables in your DynamoDB, 38 00:01:20,811 --> 00:01:23,327 and so our applications basically, 39 00:01:23,327 --> 00:01:25,057 instead of talking straight to DynamoDB 40 00:01:25,057 --> 00:01:26,719 they are going to interact with the 41 00:01:26,719 --> 00:01:28,601 Amazon DynamoDB accelerator, 42 00:01:28,601 --> 00:01:30,767 so no code change, just straight interaction 43 00:01:30,767 --> 00:01:33,359 with the DynamoDB accelerator. 44 00:01:33,359 --> 00:01:35,310 The accelerator itself will interact 45 00:01:35,310 --> 00:01:37,219 with your DynamoDB databases, 46 00:01:37,219 --> 00:01:40,155 and it will be smart enough to cache whatever is needed, 47 00:01:40,155 --> 00:01:41,487 whenever it is needed. 48 00:01:41,487 --> 00:01:43,073 So it's a very simple concept, 49 00:01:43,073 --> 00:01:45,809 it's a very easy way to cache some reads, 50 00:01:45,809 --> 00:01:48,688 and improve your application performance at minimal costs. 51 00:01:48,688 --> 00:01:51,223 To enable DAX, nothing easier. 52 00:01:51,223 --> 00:01:53,085 We just go to DAX on the left hand side, 53 00:01:53,085 --> 00:01:55,431 and you have a DAX enabled region for it, 54 00:01:55,431 --> 00:01:57,150 you see this left hand side? 55 00:01:57,150 --> 00:01:58,794 We go to dashboard, and we see we have 56 00:01:58,794 --> 00:02:02,115 no clusters running, but we could create a cluster, 57 00:02:02,115 --> 00:02:04,681 we could name it you say, "mychache," 58 00:02:04,681 --> 00:02:06,657 and then you specify the type of nodes you want. 59 00:02:06,657 --> 00:02:09,179 So obviously, you can have some very small instances 60 00:02:09,179 --> 00:02:10,975 like t2.small, t2.medium, but you can go 61 00:02:10,975 --> 00:02:13,681 all the way to r4.16xlarge if you have 62 00:02:13,681 --> 00:02:16,996 a very, very heavy application for reads. 63 00:02:16,996 --> 00:02:18,461 You select the cluster size, 64 00:02:18,461 --> 00:02:20,393 so you can go from one to 10 nodes, 65 00:02:20,393 --> 00:02:22,635 and greater nodes gives you better availability, 66 00:02:22,635 --> 00:02:24,857 and better performance for read scale. 67 00:02:24,857 --> 00:02:27,053 You can enable encryption for you data 68 00:02:27,053 --> 00:02:28,725 to be protected at rest. 69 00:02:28,725 --> 00:02:30,593 You need to give an IAM role to DAX, 70 00:02:30,593 --> 00:02:33,645 and this IAM role must be granted the access 71 00:02:33,645 --> 00:02:35,821 to your DynamoDB tables. 72 00:02:35,821 --> 00:02:37,597 Then you need to select a subnet group, 73 00:02:37,597 --> 00:02:39,829 which is where your DAX cluster will be 74 00:02:39,829 --> 00:02:41,483 created in your VPC. 75 00:02:41,483 --> 00:02:44,067 And you can assign some security groups, as well. 76 00:02:44,067 --> 00:02:45,681 Finally for the cluster setting, 77 00:02:45,681 --> 00:02:46,817 you can use a default setting which 78 00:02:46,817 --> 00:02:50,106 gives you a TTL of five minutes, 79 00:02:50,106 --> 00:02:51,593 no preference for availability zones, 80 00:02:51,593 --> 00:02:53,282 no preference for maintenance windows, 81 00:02:53,282 --> 00:02:54,778 so your cluster will be taken down 82 00:02:54,778 --> 00:02:56,922 from time to time, but one node at a time, 83 00:02:56,922 --> 00:02:57,891 and no notification. 84 00:02:57,891 --> 00:02:59,780 But you can change all these things. 85 00:02:59,780 --> 00:03:01,338 I'm not going to go ahead and create this, 86 00:03:01,338 --> 00:03:02,582 because this will cost money 87 00:03:02,582 --> 00:03:04,009 even if you use a t2.small, 88 00:03:04,009 --> 00:03:05,453 DAX is not in the free tier. 89 00:03:05,453 --> 00:03:06,594 But I just wanted to show you how easy 90 00:03:06,594 --> 00:03:09,032 it was to just create a DAX cluster. 91 00:03:09,032 --> 00:03:10,438 So that's it for this lecture, 92 00:03:10,438 --> 00:03:13,113 I hope you liked it, and I will see you in the next lecture.