demo · v134
Per-Context Contribution Limits
Pre-134, Shared Storage callers shared one global Private Aggregation budget — a noisy caller could starve everyone else. v134 gives each context (each Shared Storage caller origin) its own contribution budget. The planner below shows the difference for a stack of competing callers and links to the worklet-backed runner.
Heads up
Privacy Sandbox API — exercised against real reporting infra requires enrollment and
chrome://flags/#shared-storage-api. Use the sibling budget-tuning page to run the real Shared Storage worklet path where the browser exposes it.
probing privateAggregation in Shared Storage worklet...
Try it — budgeting planner
3 callers want to send contributions:
pre-134 — one global budget
v134+ — each caller has its own
The code
// inside a Shared Storage worklet (caller A):
class ReportA {
async run() {
privateAggregation.contributeToHistogram({ bucket: 1n, value: 400 });
}
}
register("report-a", ReportA);
// Pre-134: A's 400 consumed the shared global budget,
// B and C may get dropped.
// v134+: A's 400 consumed A's per-context budget;
// B and C have their own.