Managed Vendor Service Versus Self-Hosted Open Source
TradeoffPrincipalUpdated
Your event streaming moves 3 GB per second, the managed service bill is $4M a year and growing 60% annually, and you already employ six engineers who run streaming infrastructure.
Short answer: Self-Hosted Open Source. Run the open source system yourself, because at this volume the vendor's margin exceeds the cost of the team you already have.
The Two Options
A
Managed Vendor Service
B
Self-Hosted Open Source
Drill This: Your Pick First
The Better Pick
Option B
Self-Hosted Open Source
Run the open source system yourself, because at this volume the vendor's margin exceeds the cost of the team you already have. Six experienced engineers can operate large clusters, and owning the stack removes the pricing leverage the vendor holds at every renewal. Plan it as a staged migration with dual writes, and budget for the on-call load it adds.
When the Other One Wins
Managed Vendor Service
When usage is modest or no one on staff has run the system at scale, the managed service is cheaper once you count salaries, on-call, and the outages a new team will cause.