Memory sizing: measured scope and safe use

This page gives observed AX42 reference slopes, not a portable memory reservation formula. The D0 baseline used source 906aa24cc22ad6b50b824120ed6364208484203a and workflow 9c533d1de5a25b83bcb294e5b939064737b7d9fc; its complete archived grid contains three independent processes per shape. The D4 candidate has a different SHA and may not inherit a D0 numerical improvement claim. Keep the workload, allocator, protocol, TLS setting, instrumentation, host admission and exact phase fixed before comparing numbers.

For the D0 M1 shape grid, the table uses the median steady process RSS at 50,000 and 250,000 keys. The marginal figure is (median RSS at 250k - median RSS at 50k) / 200k; it includes the stored value plus key, metadata, indexes and allocator effects in this scenario.

The D0 M6 TLS-enabled HC/2 connection grid, with no slow consumers, had median steady RSS of 22.4 MiB at 100 connections and 62.0 MiB at 1,000 connections. The observed marginal slope over that interval was 46,171 RSS bytes per additional connection. The 100-connection/100-slow- consumer cell had 22.4 MiB median RSS; this does not establish that slow clients are free under other traffic or queue pressure. See the M6 raw evidence and redaction receipt.

Do not extrapolate either slope to a different value distribution, connection protocol, TLS profile, service mix, persistence mode, allocator or host. For a deployment estimate, start from the same-profile process floor, add a measured key/value marginal term and a measured connection term, then reserve separate headroom for allocator fragmentation, transient queues, file/page cache, kernel slab, background services and recovery. Validate the complete process and cgroup under the expected peak cardinality and pressure; the conservative W2a retained-byte estimate is an accounting signal, not a replacement for a process/cgroup memory limit. Do not turn these D0 observations into a universal per-key budget or a 0.71 candidate RSS claim.

The D4 evidence index proves exact-source qualification of the memory scenarios. It does not claim a numerical RSS win: the D3 foundation and safety proposals explicitly forbid that claim, and optional efficiency work is deferred under the release policy. A future profile or allocator change needs its own preregistered paired campaign before this guidance can be updated for that candidate.