在/var/lib/mongodb/中有很多WiredTigerStat.XX.XX文件。我可以删除它们吗？mongo.conf:systemLog:path:/var/log/mongodb/mongod.logdestination:filenet:bindIp:127.0.0.1security:authorization:enabledstorage:dbPath:/var/lib/mongodbjournal:enabled:trueengine:wiredTiger#wiredTiger:#engineConfig:#statisticsLogDelaySecs:30ope