add periodic snapshot reset

deploy/arm64-installer/.env.example

@@ -42,6 +42,12 @@ CLEAN_TMP_AFTER_RUN=0
 OUTPUT_COMPACT_REPORT=1
 ALLOW_RSYNC_MIRROR_REUSE=1
 FAILURE_SNAPSHOT_RESET=1
+# Periodic snapshot reset of active state DB.
+# 0: keep existing behavior.
+# 1: after one successful snapshot, allow at most N successful delta runs;
+#    the next run is forced to snapshot and active state/db is rebuilt from empty.
+PERIODIC_SNAPSHOT_RESET=0
+PERIODIC_SNAPSHOT_MAX_DELTAS=100
 DB_STATS_EXACT_EVERY=0
 
 # Validation and performance options aligned with current optimized soak defaults.

deploy/arm64-installer/docs/README.en.md

@@ -26,6 +26,8 @@ Defaults:
 - `INTERVAL_SECS=600`
 - `TAL_INPUT_MODE=file-live-ta`
 - `LIVE_TA_REFRESH_BEFORE_SNAPSHOT=1`
+- `PERIODIC_SNAPSHOT_RESET=0`
+- `PERIODIC_SNAPSHOT_MAX_DELTAS=100`
 - `HOST_DATA_DIR=/var/lib/ours-rp-arm64`
 - `SOAK_RESTART_POLICY=unless-stopped`
 - `MONITOR_PLATFORM=linux/arm64`
@@ -69,6 +71,31 @@ Default host directory:
 
 Each `runs/run_XXXX/` directory contains `report.json`, `result.ccr`, `input.cir`, `vrps.csv`, `vaps.csv`, `stage-timing.json`, logs and metadata.
 
+## Periodic Snapshot Reset
+
+New knobs:
+
+```bash
+PERIODIC_SNAPSHOT_RESET=0
+PERIODIC_SNAPSHOT_MAX_DELTAS=100
+```
+
+Semantics:
+
+- disabled by default, keeping previous behavior unchanged;
+- when enabled, one successful snapshot is followed by at most `N` successful delta runs;
+- after the threshold is reached, the next run is forced to snapshot;
+- before that forced snapshot, only the active `state/db` is reset, while `runs/`, `logs/`, `state/rsync-mirror`, `.env`, and Prometheus/Grafana data are preserved;
+- after a successful forced snapshot, the old DB staging is deleted so disk usage does not keep growing elsewhere.
+
+Check the latest `run-meta.json` for:
+
+- `sync_mode`
+- `snapshot_reason`
+- `periodic_snapshot_delta_count`
+- `periodic_snapshot_forced`
+- `reset_db_cleanup_status`
+
 ## Common Commands
 
 ```bash

deploy/arm64-installer/docs/README.zh-CN.md

@@ -26,6 +26,8 @@ vim .env
 - `INTERVAL_SECS=600`
 - `TAL_INPUT_MODE=file-live-ta`
 - `LIVE_TA_REFRESH_BEFORE_SNAPSHOT=1`
+- `PERIODIC_SNAPSHOT_RESET=0`
+- `PERIODIC_SNAPSHOT_MAX_DELTAS=100`
 - `HOST_DATA_DIR=/var/lib/ours-rp-arm64`
 - `SOAK_RESTART_POLICY=unless-stopped`
 - `MONITOR_PLATFORM=linux/arm64`
@@ -69,6 +71,31 @@ GRAFANA_ADMIN_PASSWORD=admin
 
 `runs/run_XXXX/` 中包含每轮 `report.json`、`result.ccr`、`input.cir`、`vrps.csv`、`vaps.csv`、`stage-timing.json`、日志和元数据。
 
+## 定期 snapshot reset
+
+新增配置：
+
+```bash
+PERIODIC_SNAPSHOT_RESET=0
+PERIODIC_SNAPSHOT_MAX_DELTAS=100
+```
+
+语义：
+
+- 默认关闭，行为与旧版本一致；
+- 开启后，一次成功 snapshot 后最多连续执行 `N` 个成功 delta；
+- 达到阈值后，下一轮强制跑 snapshot；
+- 强制 snapshot 前只重置 active `state/db`，保留 `runs/`、`logs/`、`state/rsync-mirror`、`.env`、Prometheus/Grafana 数据；
+- 强制 snapshot 成功后旧 DB staging 会被删除，避免磁盘只是换目录继续增长。
+
+可通过最新 `run-meta.json` 中的以下字段确认：
+
+- `sync_mode`
+- `snapshot_reason`
+- `periodic_snapshot_delta_count`
+- `periodic_snapshot_forced`
+- `reset_db_cleanup_status`
+
 ## 常用命令
 
 ```bash

deploy/arm64-installer/docs/operations.en.md

@@ -48,15 +48,47 @@ Important checks:
 - latest run status;
 - metrics, Prometheus and Grafana endpoints.
 
+`status.sh` also prints:
+
+- `periodic_snapshot_reset`
+- `periodic_snapshot_max_deltas`
+
 ## Upgrade
 
-Extract the new package, reuse the existing `.env` and `HOST_DATA_DIR`, then run:
+Extract the new package into a new directory and explicitly reuse the existing `.env` through the upgrade script:
 
 ```bash
-./upgrade.sh
+./upgrade.sh --reuse-env-from /path/to/old-installer/.env
 ```
 
-Upgrade does not delete runtime data.
+If the new package directory already has a `.env`, the upgrade script keeps it.
+
+Upgrade does not delete:
+
+- `runs/`
+- `logs/`
+- `state/rsync-mirror`
+- runtime configuration referenced by `.env`
+- Prometheus / Grafana data
+
+To validate periodic forced snapshot behavior, temporarily set:
+
+```bash
+PERIODIC_SNAPSHOT_RESET=1
+PERIODIC_SNAPSHOT_MAX_DELTAS=2
+```
+
+Then confirm the latest `run-meta.json` contains:
+
+```bash
+snapshot_reason=periodic_snapshot_delta_limit
+```
+
+After validation, restore:
+
+```bash
+PERIODIC_SNAPSHOT_MAX_DELTAS=100
+```
 
 ## Cleanup
 

deploy/arm64-installer/docs/operations.zh-CN.md

@@ -48,15 +48,47 @@
 - 最新 run 状态；
 - metrics、Prometheus、Grafana endpoint。
 
+`status.sh` 还会显示：
+
+- `periodic_snapshot_reset`
+- `periodic_snapshot_max_deltas`
+
 ## 升级
 
-把新安装包解压到新目录后，可以复用旧 `.env` 和 `HOST_DATA_DIR`。执行：
+把新安装包解压到新目录后，推荐通过升级脚本显式复用旧 `.env`：
 
 ```bash
-./upgrade.sh
+./upgrade.sh --reuse-env-from /path/to/old-installer/.env
 ```
 
-升级不会删除运行数据。
+如果新目录已经存在 `.env`，升级脚本会保留它，不覆盖。
+
+升级不会删除以下数据：
+
+- `runs/`
+- `logs/`
+- `state/rsync-mirror`
+- `.env` 对应的运行配置
+- Prometheus / Grafana 数据
+
+验证定期 forced snapshot 时，可临时设置：
+
+```bash
+PERIODIC_SNAPSHOT_RESET=1
+PERIODIC_SNAPSHOT_MAX_DELTAS=2
+```
+
+然后检查最新 `run-meta.json` 应出现：
+
+```bash
+snapshot_reason=periodic_snapshot_delta_limit
+```
+
+验证完成后恢复：
+
+```bash
+PERIODIC_SNAPSHOT_MAX_DELTAS=100
+```
 
 ## 清理
 

deploy/arm64-installer/docs/troubleshooting.en.md

@@ -66,3 +66,18 @@ For finite tests, set:
 ```bash
 SOAK_RESTART_POLICY=no
 ```
+
+## How to Confirm a Periodic Forced Snapshot
+
+Check the latest run metadata:
+
+```bash
+latest="$(find ${HOST_DATA_DIR}/runs -maxdepth 1 -type d -name 'run_*' | sort | tail -1)"
+jq '{run_id,sync_mode,snapshot_reason,periodic_snapshot_delta_count,periodic_snapshot_forced,reset_db_cleanup_status}' "$latest/run-meta.json"
+```
+
+For a threshold-triggered reset you should see:
+
+- `sync_mode: "snapshot"`
+- `snapshot_reason: "periodic_snapshot_delta_limit"`
+- `periodic_snapshot_forced: true`

deploy/arm64-installer/docs/troubleshooting.zh-CN.md

@@ -66,3 +66,18 @@ GRAFANA_ADMIN_PASSWORD=admin
 ```bash
 SOAK_RESTART_POLICY=no
 ```
+
+## 如何确认触发了定期 forced snapshot
+
+检查最新 run metadata：
+
+```bash
+latest="$(find ${HOST_DATA_DIR}/runs -maxdepth 1 -type d -name 'run_*' | sort | tail -1)"
+jq '{run_id,sync_mode,snapshot_reason,periodic_snapshot_delta_count,periodic_snapshot_forced,reset_db_cleanup_status}' "$latest/run-meta.json"
+```
+
+阈值触发时应看到：
+
+- `sync_mode: "snapshot"`
+- `snapshot_reason: "periodic_snapshot_delta_limit"`
+- `periodic_snapshot_forced: true`

deploy/arm64-installer/status.sh

@@ -29,6 +29,8 @@ echo "platform=$RPKI_PLATFORM"
 echo "rirs=${RIRS:-}"
 echo "max_runs=${MAX_RUNS:-}"
 echo "interval_secs=${INTERVAL_SECS:-}"
+echo "periodic_snapshot_reset=${PERIODIC_SNAPSHOT_RESET:-0}"
+echo "periodic_snapshot_max_deltas=${PERIODIC_SNAPSHOT_MAX_DELTAS:-100}"
 echo
 if command -v docker >/dev/null 2>&1; then
   docker version --format 'docker={{.Server.Version}}' 2>/dev/null || echo "docker=unavailable"

deploy/arm64-installer/upgrade.sh

@@ -4,7 +4,42 @@ SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 # shellcheck source=scripts/common.sh
 source "$SCRIPT_DIR/scripts/common.sh"
 
+REUSE_ENV_FROM=""
+
+usage() {
+  cat <<'USAGE'
+Usage: ./upgrade.sh [--reuse-env-from /path/to/.env]
+USAGE
+}
+
+while [[ $# -gt 0 ]]; do
+  case "$1" in
+    --reuse-env-from)
+      REUSE_ENV_FROM="$2"
+      shift 2
+      ;;
+    -h|--help)
+      usage
+      exit 0
+      ;;
+    *)
+      die "unknown option: $1"
+      ;;
+  esac
+done
+
+if [[ -n "$REUSE_ENV_FROM" ]]; then
+  [[ -f "$REUSE_ENV_FROM" ]] || die "missing reuse env file: $REUSE_ENV_FROM"
+  if [[ ! -f "$ENV_FILE" ]]; then
+    cp "$REUSE_ENV_FROM" "$ENV_FILE"
+    log "copied existing env into new package: $REUSE_ENV_FROM -> $ENV_FILE"
+  else
+    log "keeping existing env at $ENV_FILE; reuse source ignored: $REUSE_ENV_FROM"
+  fi
+fi
+
 load_env
+create_data_dirs
 install_docker_if_missing
 load_installer_images
 ensure_binfmt_if_needed

scripts/soak/run_soak.sh

@@ -22,6 +22,8 @@ OUTPUT_COMPACT_REPORT="${OUTPUT_COMPACT_REPORT:-1}"
 ALLOW_RSYNC_MIRROR_REUSE="${ALLOW_RSYNC_MIRROR_REUSE:-1}"
 RSYNC_SCOPE="${RSYNC_SCOPE:-module-root}"
 FAILURE_SNAPSHOT_RESET="${FAILURE_SNAPSHOT_RESET:-1}"
+PERIODIC_SNAPSHOT_RESET="${PERIODIC_SNAPSHOT_RESET:-0}"
+PERIODIC_SNAPSHOT_MAX_DELTAS="${PERIODIC_SNAPSHOT_MAX_DELTAS:-100}"
 DB_STATS_EXACT_EVERY="${DB_STATS_EXACT_EVERY:-3}"
 RPKI_PROGRESS_LOG="${RPKI_PROGRESS_LOG:-1}"
 RPKI_PROGRESS_SLOW_SECS="${RPKI_PROGRESS_SLOW_SECS:-10}"
@@ -44,6 +46,7 @@ META_DIR="${META_DIR:-$STATE_ROOT/meta}"
 TMP_DIR="${TMP_DIR:-$RUN_ROOT/tmp}"
 RSYNC_MIRROR_ROOT="${RSYNC_MIRROR_ROOT:-$STATE_ROOT/rsync-mirror}"
 INVALID_ROOT="$STATE_ROOT/invalid"
+RESET_STAGING_ROOT="$STATE_ROOT/reset-staging"
 LIVE_TA_REFRESH_DIR="${LIVE_TA_REFRESH_DIR:-$META_DIR/live-ta-refresh}"
 LIVE_TA_REFRESH_CONNECT_TIMEOUT_SECS="${LIVE_TA_REFRESH_CONNECT_TIMEOUT_SECS:-15}"
 LIVE_TA_REFRESH_MAX_TIME_SECS="${LIVE_TA_REFRESH_MAX_TIME_SECS:-120}"
@@ -67,6 +70,10 @@ die() {
   exit 2
 }
 
+warn() {
+  echo "warning: $*" >&2
+}
+
 is_true() {
   case "${1:-}" in
     1|true|TRUE|yes|YES|on|ON) return 0 ;;
@@ -462,6 +469,10 @@ db_state_exists() {
   [[ -e "$DB_DIR/work-db" || -e "$DB_DIR/repo-bytes.db" ]]
 }
 
+delta_state_available() {
+  [[ -e "$DB_DIR/work-db" ]]
+}
+
 isolate_state_after_failure() {
   local previous_run_id="$1"
   local timestamp
@@ -477,6 +488,97 @@ isolate_state_after_failure() {
   INVALID_TMP_PATH="$invalid_dir/$(basename "$TMP_DIR")"
 }
 
+periodic_snapshot_delta_scan() {
+  python3 - "$RUNS_ROOT" <<'PY'
+import json
+import pathlib
+import sys
+
+runs_root = pathlib.Path(sys.argv[1])
+delta_count = 0
+run_dirs = sorted(
+    [path for path in runs_root.glob("run_[0-9][0-9][0-9][0-9]") if path.is_dir()],
+    reverse=True,
+)
+for run_dir in run_dirs:
+    meta_path = run_dir / "run-meta.json"
+    summary_path = run_dir / "run-summary.json"
+    try:
+        with meta_path.open("r", encoding="utf-8") as handle:
+            meta = json.load(handle)
+        with summary_path.open("r", encoding="utf-8") as handle:
+            summary = json.load(handle)
+    except Exception as exc:
+        print(f"error\t{delta_count}\t{run_dir.name}\tjson_parse:{exc.__class__.__name__}")
+        sys.exit(0)
+    if meta.get("status") != "success" or summary.get("status") != "success":
+        continue
+    sync_mode = meta.get("sync_mode") or meta.get("syncMode")
+    if sync_mode == "delta":
+        delta_count += 1
+        continue
+    if sync_mode == "snapshot":
+        print(f"ok\t{delta_count}\t{run_dir.name}\t")
+        sys.exit(0)
+    print(f"error\t{delta_count}\t{run_dir.name}\tmissing_sync_mode")
+    sys.exit(0)
+print(f"error\t{delta_count}\t\tmissing_success_snapshot")
+PY
+}
+
+periodic_snapshot_force_needed() {
+  PERIODIC_SCAN_STATUS=""
+  PERIODIC_SCAN_DELTA_COUNT=""
+  PERIODIC_SCAN_SNAPSHOT_RUN_ID=""
+  PERIODIC_SCAN_DETAIL=""
+  local scan_output
+  scan_output="$(periodic_snapshot_delta_scan)"
+  IFS=$'\t' read -r PERIODIC_SCAN_STATUS PERIODIC_SCAN_DELTA_COUNT PERIODIC_SCAN_SNAPSHOT_RUN_ID PERIODIC_SCAN_DETAIL <<< "$scan_output"
+  if [[ "$PERIODIC_SCAN_STATUS" != "ok" ]]; then
+    warn "periodic snapshot reset scan skipped status=${PERIODIC_SCAN_STATUS:-missing} snapshot_run=${PERIODIC_SCAN_SNAPSHOT_RUN_ID:-none} detail=${PERIODIC_SCAN_DETAIL:-unknown}"
+    return 1
+  fi
+  [[ -n "$PERIODIC_SCAN_DELTA_COUNT" ]] || PERIODIC_SCAN_DELTA_COUNT="0"
+  (( PERIODIC_SCAN_DELTA_COUNT >= PERIODIC_SNAPSHOT_MAX_DELTAS ))
+}
+
+prepare_periodic_reset_state_db() {
+  local run_id="$1"
+  RESET_DB_STAGING_PATH=""
+  RESET_DB_CLEANUP_STATUS=""
+  db_state_exists || return 0
+  local timestamp
+  local staging_root
+  timestamp="$(date -u +%Y%m%dT%H%M%SZ)"
+  staging_root="$RESET_STAGING_ROOT/${run_id}-${timestamp}"
+  mkdir -p "$staging_root"
+  mv "$DB_DIR" "$staging_root/"
+  mkdir -p "$DB_DIR"
+  RESET_DB_STAGING_PATH="$staging_root/$(basename "$DB_DIR")"
+  RESET_DB_CLEANUP_STATUS="pending"
+}
+
+finalize_periodic_reset_state_db() {
+  local final_status="$1"
+  local reset_db_staging_path="$2"
+  [[ -n "$reset_db_staging_path" ]] || {
+    printf '%s\n' ""
+    return 0
+  }
+  local staging_root
+  staging_root="$(dirname "$reset_db_staging_path")"
+  if [[ "$final_status" == "success" ]]; then
+    if rm -rf "$staging_root"; then
+      printf '%s\n' "deleted"
+      return 0
+    fi
+    warn "failed to delete periodic reset staging: $staging_root"
+    printf '%s\n' "cleanup_failed"
+    return 1
+  fi
+  printf '%s\n' "retained_failure"
+}
+
 write_run_meta() {
   local output_path="$1"
   local status="$2"
@@ -494,10 +596,18 @@ write_run_meta() {
   local daemon_exit_code="${14}"
   local package_root="${15}"
   local env_file="${16}"
+  local periodic_snapshot_reset_enabled="${17}"
+  local periodic_snapshot_max_deltas="${18}"
+  local periodic_snapshot_delta_count="${19}"
+  local periodic_snapshot_forced="${20}"
+  local reset_db_staging_path="${21}"
+  local reset_db_cleanup_status="${22}"
   python3 - "$output_path" "$status" "$run_index" "$run_id" "$sync_mode" "$snapshot_reason" \
     "$previous_run_id" "$previous_run_success_value" "$started_at" "$completed_at" \
     "$invalid_db_path" "$invalid_state_path" "$invalid_tmp_path" "$daemon_exit_code" \
-    "$package_root" "$env_file" <<'PY'
+    "$package_root" "$env_file" "$periodic_snapshot_reset_enabled" \
+    "$periodic_snapshot_max_deltas" "$periodic_snapshot_delta_count" \
+    "$periodic_snapshot_forced" "$reset_db_staging_path" "$reset_db_cleanup_status" <<'PY'
 import json
 import sys
 
@@ -514,6 +624,9 @@ def nullable_int(value):
         return None
     return int(value)
 
+def bool_value(value):
+    return value == "true"
+
 (
     output_path,
     status,
@@ -531,6 +644,12 @@ def nullable_int(value):
     daemon_exit_code,
     package_root,
     env_file,
+    periodic_snapshot_reset_enabled,
+    periodic_snapshot_max_deltas,
+    periodic_snapshot_delta_count,
+    periodic_snapshot_forced,
+    reset_db_staging_path,
+    reset_db_cleanup_status,
 ) = sys.argv[1:]
 
 data = {
@@ -549,6 +668,12 @@ data = {
     "daemon_exit_code": nullable_int(daemon_exit_code),
     "package_root": package_root,
     "env_file": env_file,
+    "periodic_snapshot_reset_enabled": bool_value(periodic_snapshot_reset_enabled),
+    "periodic_snapshot_max_deltas": int(periodic_snapshot_max_deltas),
+    "periodic_snapshot_delta_count": nullable_int(periodic_snapshot_delta_count),
+    "periodic_snapshot_forced": bool_value(periodic_snapshot_forced),
+    "reset_db_staging_path": nullable(reset_db_staging_path),
+    "reset_db_cleanup_status": nullable(reset_db_cleanup_status),
 }
 with open(output_path, "w", encoding="utf-8") as handle:
     json.dump(data, handle, indent=2, sort_keys=True)
@@ -796,7 +921,9 @@ run_one_round() {
   started_at="$(date -u +%Y-%m-%dT%H:%M:%SZ)"
   write_run_meta "$run_dir/run-meta.json" "running" "$run_index" "$run_id" "$sync_mode" \
     "$snapshot_reason" "$previous_run_id" "$previous_success_value" "$started_at" "" \
-    "$INVALID_DB_PATH" "$INVALID_STATE_PATH" "$INVALID_TMP_PATH" "" "$PACKAGE_ROOT" "$ENV_FILE"
+    "$INVALID_DB_PATH" "$INVALID_STATE_PATH" "$INVALID_TMP_PATH" "" "$PACKAGE_ROOT" "$ENV_FILE" \
+    "$RUN_META_PERIODIC_ENABLED" "$RUN_META_PERIODIC_MAX_DELTAS" "$RUN_META_PERIODIC_DELTA_COUNT" \
+    "$RUN_META_PERIODIC_FORCED" "$RUN_META_RESET_DB_STAGING_PATH" "$RUN_META_RESET_DB_CLEANUP_STATUS"
 
   prepare_live_ta_inputs_for_run "$run_id" "$sync_mode"
   build_child_args
@@ -839,9 +966,18 @@ run_one_round() {
   if [[ "$daemon_exit_code" -eq 0 && "$summary_state" == "success" ]]; then
     final_status="success"
   fi
+  if [[ -n "$RUN_META_RESET_DB_STAGING_PATH" ]]; then
+    if RUN_META_RESET_DB_CLEANUP_STATUS="$(finalize_periodic_reset_state_db "$final_status" "$RUN_META_RESET_DB_STAGING_PATH")"; then
+      :
+    else
+      final_status="failed"
+    fi
+  fi
   write_run_meta "$run_dir/run-meta.json" "$final_status" "$run_index" "$run_id" "$sync_mode" \
     "$snapshot_reason" "$previous_run_id" "$previous_success_value" "$started_at" "$completed_at" \
-    "$INVALID_DB_PATH" "$INVALID_STATE_PATH" "$INVALID_TMP_PATH" "$daemon_exit_code" "$PACKAGE_ROOT" "$ENV_FILE"
+    "$INVALID_DB_PATH" "$INVALID_STATE_PATH" "$INVALID_TMP_PATH" "$daemon_exit_code" "$PACKAGE_ROOT" "$ENV_FILE" \
+    "$RUN_META_PERIODIC_ENABLED" "$RUN_META_PERIODIC_MAX_DELTAS" "$RUN_META_PERIODIC_DELTA_COUNT" \
+    "$RUN_META_PERIODIC_FORCED" "$RUN_META_RESET_DB_STAGING_PATH" "$RUN_META_RESET_DB_CLEANUP_STATUS"
   printf '%s\n' "$run_id" > "$META_DIR/last-run-id"
   if is_true "$CLEAN_TMP_AFTER_RUN"; then
     rm -rf "$daemon_state_root"
@@ -869,6 +1005,7 @@ main() {
   validate_positive_int "RETAIN_RUNS" "$RETAIN_RUNS"
   validate_rsync_scope
   validate_tal_input_mode
+  validate_non_negative_int "PERIODIC_SNAPSHOT_MAX_DELTAS" "$PERIODIC_SNAPSHOT_MAX_DELTAS"
   if [[ -n "${DB_STATS_EXACT_EVERY:-}" && "$DB_STATS_EXACT_EVERY" != "0" ]]; then
     validate_positive_int "DB_STATS_EXACT_EVERY" "$DB_STATS_EXACT_EVERY"
   fi
@@ -889,7 +1026,7 @@ main() {
     fi
   done
 
-  mkdir -p "$RUNS_ROOT" "$LOG_ROOT" "$DB_DIR" "$META_DIR" "$TMP_DIR" "$INVALID_ROOT" "$LIVE_TA_REFRESH_DIR"
+  mkdir -p "$RUNS_ROOT" "$LOG_ROOT" "$DB_DIR" "$META_DIR" "$TMP_DIR" "$INVALID_ROOT" "$RESET_STAGING_ROOT" "$LIVE_TA_REFRESH_DIR"
   if is_true "$ALLOW_RSYNC_MIRROR_REUSE"; then
     mkdir -p "$RSYNC_MIRROR_ROOT"
   fi
@@ -918,6 +1055,22 @@ main() {
     INVALID_DB_PATH=""
     INVALID_STATE_PATH=""
     INVALID_TMP_PATH=""
+    PERIODIC_SCAN_STATUS=""
+    PERIODIC_SCAN_DELTA_COUNT=""
+    PERIODIC_SCAN_SNAPSHOT_RUN_ID=""
+    PERIODIC_SCAN_DETAIL=""
+    RESET_DB_STAGING_PATH=""
+    RESET_DB_CLEANUP_STATUS=""
+    if is_true "$PERIODIC_SNAPSHOT_RESET"; then
+      RUN_META_PERIODIC_ENABLED="true"
+    else
+      RUN_META_PERIODIC_ENABLED="false"
+    fi
+    RUN_META_PERIODIC_MAX_DELTAS="$PERIODIC_SNAPSHOT_MAX_DELTAS"
+    RUN_META_PERIODIC_DELTA_COUNT=""
+    RUN_META_PERIODIC_FORCED="false"
+    RUN_META_RESET_DB_STAGING_PATH=""
+    RUN_META_RESET_DB_CLEANUP_STATUS=""
     local previous_run_id=""
     local previous_success_value=""
     local sync_mode="snapshot"
@@ -926,8 +1079,24 @@ main() {
       previous_run_id="$(printf 'run_%04d' $((next_index - 1)))"
       if previous_run_success "$RUNS_ROOT/$previous_run_id"; then
         previous_success_value="true"
-        if [[ -e "$DB_DIR/work-db" ]]; then
+        if delta_state_available; then
           sync_mode="delta"
+          if is_true "$PERIODIC_SNAPSHOT_RESET"; then
+            if periodic_snapshot_force_needed; then
+              RUN_META_PERIODIC_DELTA_COUNT="$PERIODIC_SCAN_DELTA_COUNT"
+              RUN_META_PERIODIC_FORCED="true"
+              sync_mode="snapshot"
+              snapshot_reason="periodic_snapshot_delta_limit"
+              prepare_periodic_reset_state_db "$(printf 'run_%04d' "$next_index")"
+              RUN_META_RESET_DB_STAGING_PATH="$RESET_DB_STAGING_PATH"
+              RUN_META_RESET_DB_CLEANUP_STATUS="$RESET_DB_CLEANUP_STATUS"
+              echo "periodic snapshot reset forcing snapshot run=$(printf 'run_%04d' "$next_index") delta_count=$PERIODIC_SCAN_DELTA_COUNT max_deltas=$PERIODIC_SNAPSHOT_MAX_DELTAS"
+            else
+              if [[ "$PERIODIC_SCAN_STATUS" == "ok" ]]; then
+                RUN_META_PERIODIC_DELTA_COUNT="$PERIODIC_SCAN_DELTA_COUNT"
+              fi
+            fi
+          fi
         else
           sync_mode="snapshot"
           snapshot_reason="missing_db"