我正在使用复制槽，用于备用服务器的流式复制。pg_xlog 文件越来越疯狂。我检查了 max_wal_size 和 wal_keep_segment 配置，它们看起来都很合理。有没有办法删除应用的日志？
# - Checkpoints -
#checkpoint_timeout = 5min # range 30s-1h
max_wal_size = 2GB
min_wal_size = 1GB
checkpoint_completion_target = 0.7
# checkpoint target duration, 0.0 - 1.0
#checkpoint_warning = 30s
# 0 disables
当我尝试查看 checkpoint_segments 时；
postgres=# show checkpoint_segments;
ERROR: unrecognized configuration parameter "checkpoint_segments"
备用数据库的最后一个日志可能是相关的；
2017-03-08 15:13:18 +03 [43578-3] postgres@e ERROR: current
transaction is aborted, commands ignored until end of transaction block
2017-03-08 15:13:18 +03 [43578-4] postgres@e STATEMENT: SELECT NULL AS TABLE_CAT, n.nspname AS TABLE_SCHEM, c.relname AS TABLE_NAME, CASE n.nspname ~ '^pg_' OR n.nspname = 'information_schema' WHE$