Event replay cost: what it costs to run history again
Archiving events is cheap. Replaying them runs your entire downstream pipeline a second time at full price. Here is what archives, retention, and a replay actually cost.
The C3X Team··6 min read
Blog, page 6
Cloud Cost Engineering and Open Source FinOps
Notes from the team building C3X. Cost estimation for Terraform, the economics of cloud infrastructure, and how to ship FinOps tooling without a SaaS gate.
Serverless cost per tenant: attributing a shared function bill
Serverless pricing is per request, which makes per-tenant attribution possible in a way shared servers never allow. Doing it well requires instrumenting the right dimensions. Here is the method.
The C3X Team··7 min read
Chatty function chains: what waiting costs in serverless
When one function calls another synchronously, you pay for both at once. Chains of waiting functions are the most expensive common anti-pattern in serverless, and they are easy to spot.
The C3X Team··6 min read
Functions in a VPC: what network attachment really costs
Putting a function in a VPC is free in itself. What it pulls in is not: a NAT gateway for outbound access, data processing charges, and the choice between endpoints and gateways. Here is the bill.
The C3X Team··7 min read
SQS FIFO versus standard: what ordering costs per message
FIFO queues cost 25 percent more per request, but the real price difference is throughput, batching behaviour, and the downstream design ordering forces. Here is the full comparison.
The C3X Team··6 min read
PgBouncer vs RDS Proxy: what connection pooling actually costs
A managed proxy bills per vCPU-hour of the database it fronts. A self-hosted pooler bills as a small container. Both let you run a smaller database instance, which is where the real money is. Here is the arithmetic.
The C3X Team··7 min read
Read replica or cache: which one actually costs less per read
A read replica is a full copy of your database with a full copy of its price. A cache node is a fraction of that. The choice comes down to hit ratio, data freshness, and how many distinct queries you are serving. Here is the cost-per-read math.
The C3X Team··7 min read
Cloud SQL vs RDS for PostgreSQL: a line-by-line cost comparison
Google prices Cloud SQL by vCPU and GB separately; AWS prices RDS by fixed instance shape. That single difference changes which cloud is cheaper for your particular ratio of CPU to memory. Here is the comparison at real prices.
The C3X Team··7 min read
MySQL vs PostgreSQL on managed services: does the engine change the bill?
The per-hour rates for managed MySQL and PostgreSQL are nearly identical on every major cloud. The cost difference shows up somewhere else entirely: in how each engine uses storage, connections, and replication. Here is where it actually lands.
The C3X Team··7 min read
MongoDB Atlas vs self-hosted: the real cost of managing it yourself
Atlas M30 costs about $394 per month. The same three-node replica set on EC2 costs about $230 in instances. The $164 gap is not the whole story, and for most teams it is not even the important part. Here is the full accounting.
The C3X Team··7 min read
Sizing a Redis cache: how much memory you actually need to buy
Most Redis clusters are sized by guess and run at 20 percent memory utilization. Sizing from working set, eviction policy, and replication overhead usually lets you drop two node sizes and save several hundred dollars a month.
The C3X Team··7 min read
Database storage autoscaling: the ratchet nobody budgets for
Storage autoscaling grows your database disk automatically and never shrinks it. A one-off bulk load can leave you paying for terabytes you deleted years ago. Here is how the ratchet works and what it costs.
The C3X Team··6 min read
Provisioned IOPS for databases: when paying for I/O is worth it
io2 Block Express charges $0.065 per provisioned IOPS per month on top of storage. Provision 40,000 IOPS and you have added $2,600 to the monthly bill before a single byte is stored. Here is when that is the right call.
The C3X Team··7 min read
Point-in-time recovery cost: what continuous backup really charges
PITR is billed on change volume, not database size, which is why a small write-heavy database can cost more to back up than a large static one. Here is how the meters work across AWS, Azure, and GCP.
The C3X Team··7 min read
Manual database snapshot sprawl: the graveyard on your invoice
Manual snapshots never expire. Every pre-migration safety copy taken over five years is still billing. A typical mid-sized account holds hundreds of gigabytes of snapshots nobody could name the purpose of.
The C3X Team··6 min read
High availability databases: what the second node really buys
HA doubles compute and storage on every major cloud, so the question is not whether availability is good but what outage cost the second node avoids. Here is how to do that arithmetic honestly.
The C3X Team··7 min read
A method for right-sizing database instances that actually works
CPU utilization alone is a bad sizing signal for databases, because the binding constraint is usually memory or connections. Here is a four-signal method that produces a defensible instance choice instead of a guess.
The C3X Team··7 min read
Serverless database idle cost: what you pay to do nothing
Serverless databases promise you pay only for what you use, but most of them have a floor. Understanding the minimum capacity charge is the difference between a $5 development database and a $44 one.
The C3X Team··7 min read
Autovacuum and the cost of maintenance you are not doing
Autovacuum tuning is usually framed as a performance topic. It is also a storage bill: dead tuples on a ratcheting volume become permanent cost, and a badly tuned vacuum can add 40 percent to your database size.
The C3X Team··7 min read
Query optimization as a cost lever: the cheapest capacity you can buy
Adding an index that turns a sequential scan into a lookup can remove more load than doubling your instance size, and it costs one afternoon rather than $378 a month forever. Here is how to find the queries worth fixing.
The C3X Team··7 min read
Index bloat: the storage line hiding inside your database size
Indexes routinely occupy more space than the tables they serve, and a bloated or duplicated index set can be half your database volume. Here is how to measure it and what removing it is worth.
The C3X Team··6 min read
Database migration cost planning: what the project actually bills
A migration is not a one-line move. You pay for both databases in parallel, for replication tooling, for cross-region transfer, and for the oversized target you provisioned to be safe. Here is a budget that holds.
The C3X Team··7 min read
Development and test databases: the quiet half of your database bill
Non-production databases often outnumber production ones five to one and run identical configurations. Scheduling, sizing, and sharing them typically cuts that spend by 70 to 85 percent with no impact on anyone's work.
The C3X Team··7 min read
Building a cloud cost business case that finance approves
A cost optimization program needs funding, headcount, and engineering time, and none of that arrives without a business case. Here is how to size the opportunity, model the investment, and write the one page that gets a yes.
The C3X Team··7 min read