# =============================================================================
#  settings.conf - every tunable value for the DNS kit, in one place
# =============================================================================
#  Both start-dns.sh and test-dns.sh read this file.
#  Edit a value here, then re-run ./start-dns.sh so BIND picks it up.
#
#  Any value can also be overridden for a single run from the command line:
#      DURATION=30 ./test-dns.sh throughput
# =============================================================================


# -----------------------------------------------------------------------------
#  1. Where the DNS server is reached
# -----------------------------------------------------------------------------
# All test traffic stays on this machine (loopback). No traffic leaves the host.
DNS_SERVER="${DNS_SERVER:-127.0.0.1}"
DNS_PORT="${DNS_PORT:-53}"

# BIND's built-in statistics web page (JSON). The test reads server-side
# counters from it: queries received, cache hits, cache memory ...
# Port 8953 is used because SELinux on RHEL already allows named to use it
# (port type rndc_port_t), so no SELinux change is needed.
STATS_PORT="${STATS_PORT:-8953}"


# -----------------------------------------------------------------------------
#  2. Files and folders used on the server
# -----------------------------------------------------------------------------
# The kit never edits /etc/named.conf. It writes its own configuration file
# and tells named.service to use it, through one systemd drop-in file.
# "./start-dns.sh cleanup" removes all of these again.
TEST_CONF="/etc/named/perf-test.conf"
TSIG_KEY_FILE="/etc/named/perf-test-upstream.key"
ZONE_DIR="/var/named/perf-test"
SYSTEMD_DROPIN="/etc/systemd/system/named.service.d/zz-perf-test.conf"

# Test zone names. The ".test" top-level domain is reserved for testing
# (RFC 6761), so these names can never clash with real internet names.
TEST_ZONE="perf.test"            # authoritative zone, answered by this server
UPSTREAM_ZONE="upstream.test"    # zone reached through forwarding (cache test)


# -----------------------------------------------------------------------------
#  3. BIND (named) settings
# -----------------------------------------------------------------------------
# Number of host records in the test zone (host1 ... hostN). A bigger zone
# makes startup and zone-transfer (AXFR) tests more realistic.
ZONE_RECORDS="${ZONE_RECORDS:-100000}"

# Worker threads of named. Empty = BIND's default (one per CPU core).
NAMED_THREADS="${NAMED_THREADS:-}"

# Largest amount of memory the answer cache may use (BIND syntax:
# "256m", "2g", or a share of RAM like "90%", which is BIND's own default).
MAX_CACHE_SIZE="${MAX_CACHE_SIZE:-90%}"

RECURSIVE_CLIENTS="${RECURSIVE_CLIENTS:-1000}"   # parallel recursive lookups allowed
TCP_CLIENTS="${TCP_CLIENTS:-1000}"               # parallel TCP connections allowed (BIND default: 150)


# -----------------------------------------------------------------------------
#  4. How hard and how long each test runs
# -----------------------------------------------------------------------------
DURATION="${DURATION:-10}"               # seconds of load for each test run

# "Outstanding queries" = queries sent but not yet answered, at one moment.
# It is the DNS version of "number of simultaneous clients".
OUTSTANDING="${OUTSTANDING:-100}"
OUTSTANDING_LEVELS="${OUTSTANDING_LEVELS:-1 10 50 100 200 500 1000}"  # "concurrency" test steps

# Fixed query rates (queries per second) for the tests that need a steady load.
LATENCY_TEST_QPS="${LATENCY_TEST_QPS:-10000}"   # "latency": normal, steady traffic
LOSS_TEST_QPS="${LOSS_TEST_QPS:-50000}"         # "loss": your expected peak (or higher)

QUERY_TIMEOUT="${QUERY_TIMEOUT:-2}"      # seconds without answer = query lost
STARTUP_ROUNDS="${STARTUP_ROUNDS:-3}"    # restarts measured by the "startup" test
AXFR_ROUNDS="${AXFR_ROUNDS:-3}"          # zone transfers measured by the "axfr" test
CACHE_TEST_NAMES="${CACHE_TEST_NAMES:-50000}"   # different names looked up in the "cache" test

# Worker processes of the load generator (lib/dnsload.py). Each one uses up
# to one CPU core and can send about 100,000 queries per second.
# Default: a quarter of the CPU cores (1 to 8), so named keeps most of the CPUs.
DEFAULT_LOAD_PROCESSES=$(( $(nproc) / 4 ))
(( DEFAULT_LOAD_PROCESSES < 1 )) && DEFAULT_LOAD_PROCESSES=1
(( DEFAULT_LOAD_PROCESSES > 8 )) && DEFAULT_LOAD_PROCESSES=8
LOAD_PROCESSES="${LOAD_PROCESSES:-$DEFAULT_LOAD_PROCESSES}"


# -----------------------------------------------------------------------------
#  5. Pass / fail targets
# -----------------------------------------------------------------------------
#  Sensible starting points for a small RHEL 9 DNS server tested over
#  localhost. Adjust them to your own hardware and service requirements.
#  A result that misses its target is reported as FAIL; see
#  PERFORMANCE-METRICS.md for what each number means.
TARGET_STARTUP_MAX_MS="${TARGET_STARTUP_MAX_MS:-10000}"         # start until first answer
TARGET_THROUGHPUT_MIN_QPS="${TARGET_THROUGHPUT_MIN_QPS:-20000}" # queries/second, at least
TARGET_LATENCY_P95_MAX_MS="${TARGET_LATENCY_P95_MAX_MS:-2}"     # 95% of answers faster than
TARGET_LATENCY_P99_MAX_MS="${TARGET_LATENCY_P99_MAX_MS:-5}"     # 99% of answers faster than
TARGET_SCALING_MIN_PCT="${TARGET_SCALING_MIN_PCT:-50}"          # throughput kept at top level vs peak
TARGET_LOSS_MAX_PCT="${TARGET_LOSS_MAX_PCT:-0.1}"               # lost + failed queries, at most %
TARGET_TCP_MIN_QPS="${TARGET_TCP_MIN_QPS:-2000}"                # TCP, new connection per query
TARGET_CACHE_HIT_P95_MAX_MS="${TARGET_CACHE_HIT_P95_MAX_MS:-2}" # answers from cache, p95
TARGET_AXFR_MAX_S="${TARGET_AXFR_MAX_S:-10}"                    # full zone transfer, at most
TARGET_CPU_MAX_PCT="${TARGET_CPU_MAX_PCT:-90}"                  # share of all CPUs named may use
TARGET_MEMORY_MAX_MB="${TARGET_MEMORY_MAX_MB:-2048}"            # peak named memory, at most