Comparison
Blast radiusvsBulkhead
Blast radius
you ask how much of the product breaks if this one component dies, and design so the answer is not "all of it".
The scope of impact when a given component fails. Reducing it is the point of cells, shards, bulkheads and per-tenant isolation. It is also the right frame for reviewing a change: not "will this break" but "what breaks with it".
Full entry →Bulkhead
you give each downstream its own pool of connections so one slow dependency cannot consume every thread you have.
Partitioning resources so that exhaustion in one compartment cannot sink the whole service. In practice: separate connection pools, thread pools or instances per dependency or per tenant. It converts a total outage into a partial one, which is the entire goal of resilience engineering.
Full entry →