优化空闲binlog轮转

scripts/archive-binlog.sh

@@ -2,8 +2,8 @@
 set -euo pipefail
 umask 077
 
-# 分钟级 binlog 归档。每次轮转后只归档已关闭文件；每个对象以
-# server_uuid、原始文件名和原始 sha256 命名，避免实例重建后的编号碰撞。
+# 分钟级 binlog 归档。每分钟检查活动 binlog 的 Position，仅在有新增已提交事务时
+# 轮转；每个对象以 server_uuid、原始文件名和原始 sha256 命名，避免实例重建后的编号碰撞。
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 # shellcheck source=backup-common.sh
@@ -31,6 +31,29 @@ closed_binlogs() {
     2>/dev/null | awk 'NR > 1 { print previous } { previous = $1 } END { }'
 }
 
+master_status() {
+  local mysql_cid="$1"
+  docker exec "${mysql_cid}" sh -c \
+    'MYSQL_PWD="$MYSQL_ROOT_PASSWORD" mysql -uroot --protocol=socket -N -B -e "SHOW MASTER STATUS;"' \
+    2>/dev/null | awk 'NR == 1 { print $1 "\t" $2 }'
+}
+
+state_active_binlog() {
+  local state_dir="$1" key="$2" value
+  [[ -f "${state_dir}/active-binlog.env" ]] || return
+  value="$(awk -F= -v key="${key}" '$1 == key { print substr($0, index($0, "=") + 1); exit }' "${state_dir}/active-binlog.env")"
+  printf '%s' "${value}"
+}
+
+write_active_binlog_state() {
+  local state_dir="$1" filename="$2" position="$3"
+  {
+    printf 'filename=%s\n' "${filename}"
+    printf 'position=%s\n' "${position}"
+    printf 'observed_at=%s\n' "$(date -Iseconds)"
+  } > "${state_dir}/active-binlog.env"
+}
+
 state_last_index() {
   local state_dir="$1"
   local value
@@ -103,7 +126,12 @@ archive() {
   backup_require_cmd ossutil
   backup_require_cmd openssl
   require_archive_config
-  local backup_dir oss_uri mysql_cid server_uuid state_dir first_binlog last_index first_index expected_index filename index
+  local force="${1:-}" backup_dir oss_uri mysql_cid server_uuid state_dir first_binlog last_index first_index expected_index filename index
+  local current_status current_file current_pos previous_file previous_pos final_status final_file final_pos
+  if [[ -n "${force}" && "${force}" != '--force' ]]; then
+    printf '用法: %s archive [--force]\n' "$0" >&2
+    exit 1
+  fi
   backup_dir="$(backup_require_env BACKUP_DIR)"
   backup_validate_dir "${backup_dir}"
   oss_uri="$(backup_require_env BACKUP_OSS_URI)"
@@ -115,8 +143,19 @@ archive() {
   work_dir="${backup_dir}/.tmp-binlog-$$"
   mkdir -p "${state_dir}" "${work_dir}"
 
-  docker exec "${mysql_cid}" sh -c \
-    'MYSQL_PWD="$MYSQL_ROOT_PASSWORD" mysql -uroot --protocol=socket -e "FLUSH BINARY LOGS;"' >/dev/null
+  current_status="$(master_status "${mysql_cid}")"
+  IFS=$'\t' read -r current_file current_pos <<< "${current_status}"
+  [[ -n "${current_file}" && "${current_pos}" =~ ^[0-9]+$ ]] || { backup_error '无法读取当前 binlog 位点'; exit 1; }
+  backup_binlog_index "${current_file}" >/dev/null
+  previous_file="$(state_active_binlog "${state_dir}" filename || true)"
+  previous_pos="$(state_active_binlog "${state_dir}" position || true)"
+
+  if [[ "${force}" == '--force' || -z "${previous_file}" || -z "${previous_pos}" || "${current_file}" != "${previous_file}" || "${current_pos}" != "${previous_pos}" ]]; then
+    docker exec "${mysql_cid}" sh -c \
+      'MYSQL_PWD="$MYSQL_ROOT_PASSWORD" mysql -uroot --protocol=socket -e "FLUSH BINARY LOGS;"' >/dev/null
+  else
+    backup_log "活动 binlog 无新增已提交事务，跳过轮转"
+  fi
   first_binlog="$(docker exec "${mysql_cid}" sh -c \
     'MYSQL_PWD="$MYSQL_ROOT_PASSWORD" mysql -uroot --protocol=socket -N -B -e "SHOW BINARY LOGS;"' | head -1 | awk '{print $1}')"
   [[ -n "${first_binlog}" ]] || { backup_error '无法读取 binlog 列表'; exit 1; }
@@ -141,6 +180,10 @@ archive() {
     archive_one "${mysql_cid}" "${state_dir}" "${server_uuid}" "${oss_uri}" "${filename}"
     expected_index="${index}"
   done < <(closed_binlogs "${mysql_cid}")
+  final_status="$(master_status "${mysql_cid}")"
+  IFS=$'\t' read -r final_file final_pos <<< "${final_status}"
+  [[ -n "${final_file}" && "${final_pos}" =~ ^[0-9]+$ ]] || { backup_error '无法读取归档后的 binlog 位点'; exit 1; }
+  write_active_binlog_state "${state_dir}" "${final_file}" "${final_pos}"
   backup_log "binlog 归档完成，实例 ${server_uuid}"
 }
 
@@ -165,7 +208,7 @@ verify() {
 }
 
 case "${1:-archive}" in
-  archive) archive ;;
+  archive) archive "${2:-}" ;;
   verify) verify ;;
   *)
     printf '用法: %s {archive|verify}\n' "$0" >&2