One thing I hate about AWS billing is that it doesn't separate out disk costs from the VM compute. Also, is it just me or is RDS ridiculously expensive? I'm fairly new to AWS, having mostly used (and continue to use) Azure.
People still treat their databases like mainframes; just make the machine bigger to get better performance, and use more reliable components to decrease the risk of data loss or downtime. Amazon is happy to take your money to manage that for you. Their profit margin exists in you being scared of what can go wrong, and the ease of getting things set up.
(I don't have a good suggestion for an alternative to this approach. The design of commonly-used relational databases surprises me. They all assume disks have some sort of intrinsic durability. Disk manufacturers all make you pay extra money to maintain this illusion; underprovisioning, wear leveling, background garbage collection, hardware RAID. But at the end of the day, it can all just get sucked up by a tornado (or a rogue shell script) and all that means nothing. I do not understand why disks are not just dumb blocks of NAND flash connected directly to the application, which can then provide cross-datacenter redundancy and save everyone a ton of money. I guess that is why Google makes their own SSDs and their own planet-scale database engine. They know it's silly. The rest of us are stuck with expensive garbage that is, with 100% certainty, going to fail. Who to blame is all that we can work around, and blaming Amazon is better than blaming yourself!)
Distributed systems bring their own problems. I've seen more production outages caused by poorly coded or configured HA setups than due to any single-host level hardware failure. I remember one application where a 60 second network outage caused a forty minute database outage due to HA supervisors going batshit. What works well are simple setups like async log shipping to another site with manual fail-over. If you think you cannot afford 30 minutes downtime there is really no amount of money you can spend to be sure you are improving your chances.
One thing I hate about AWS billing is that it doesn't separate out disk costs from the VM compute.
Doesn't it? EBS stuff (storage and IOPS) being a separate line item last I checked. Ephemeral storage (if applicable) is included with the compute price.
Also, is it just me or is RDS ridiculously expensive? I'm fairly new to AWS, having mostly used (and continue to use) Azure.
I seem to remember it being around what an EC2 instance cost until you go to multi-AZ and then you're paying for an extra instance. But I've only used RDS with postgres and mysql type engines, none of the proprietary stuff that would add on extra licensing fees.
It may in the actual invoice, but in the dashboard it's difficult to narrow down what it actually costs when you're doing maintenance. A lot of things are just listed as EC2 (other). I can't tell what I'm saving by getting rid of a disk. In this way Azure is more friendly, at least in my experience.
Nope, the RDS instances cost quite a bit more. For example, in us-east-1, an unreserved t3.micro costs $91.104000 a year but a Postgres t3.micro costs $157.680000 a year. That particular RDS instance does not include any storage, you pay as you go with EBS.
For the m4 series, RDS is almost double the instance cost.
Yeah, RDS is pretty expensive but unlike raw compute you do get guaranteed performance.
The issue with AWS is that it's easy to add new services without finding new vendors so companies just spend more and more on AWS as features are not as important as 'cost savings'.
Disk costs at Amazon are an annoyance when you need to spin up a VM just for a few days. Apparently you pay for the entire month in advance even if you just need it for a shorter period.
Whereas Azure disk costs for VMs accrue on a daily basis.
What kind of disk costs? I'm fairly certain this is not how EBS works: you pay only for the time you have the storage provisioned. I think the granularity on that calculation goes down to the level of seconds? Much smaller units than months, at any rate.
That's not what we were finding in our bill. Maybe it's the way we provisioned the VMs or something. But we don't have this issue with Azure. We can see the daily cost associated with the disks.
Aurora is a binary compatible (Mysql, PG) API over an internal AWS infra/storage layer that provides cross-AZ redundancy and transparent scaling. Storage is replicated 6 ways across 3 AZs. You still need to define the "compute" component as an EC2 instance, but storage is not via EBS. Read replicas are compute only, storage is shared. Backups are continuous to S3.
RDS is a managed database "cluster" (in the PG sense of the word) running on EC2 infra. You need to define both compute and storage. Backups are snapshots, not PIT. Replicas are via the standard DB engine replication,
