WriteThrough

[[email protected] ~]#/opt/MegaRAID/MegaCli/MegaCli64 -cfgdsply -aall | grep Policy:
Default Cache Policy: WriteBack, ReadAhead, Cached, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAhead, Cached, No Write Cache if Bad BBU
Default Cache Policy: WriteBack, ReadAhead, Cached, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAhead, Cached, No Write Cache if Bad BBU
Default Cache Policy: WriteBack, ReadAhead, Cached, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAhead, Cached, No Write Cache if Bad BBU
Default Cache Policy: WriteBack, ReadAhead, Cached, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAhead, Cached, No Write Cache if Bad BBU
Default Cache Policy: WriteBack, ReadAhead, Cached, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAhead, Cached, No Write Cache if Bad BBU
Default Cache Policy: WriteBack, ReadAhead, Cached, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAhead, Cached, No Write Cache if Bad BBU
Default Cache Policy: WriteBack, ReadAhead, Cached, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAhead, Cached, No Write Cache if Bad BBU
Default Cache Policy: WriteBack, ReadAhead, Cached, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAhead, Cached, No Write Cache if Bad BBU

[[email protected] ~]#/opt/MegaRAID/MegaCli/MegaCli64 -LdSetProp WB -Lall -aAll

Learn cycle is active currently

So policy Change to WB will not come into effect immediately

Set Write Policy to WriteBack on Adapter 0, VD 0 (target id: 0) success
Learn cycle is active currently

So policy Change to WB will not come into effect immediately

Set Write Policy to WriteBack on Adapter 0, VD 1 (target id: 1) success
Learn cycle is active currently

So policy Change to WB will not come into effect immediately

Set Write Policy to WriteBack on Adapter 0, VD 2 (target id: 2) success
Learn cycle is active currently

So policy Change to WB will not come into effect immediately

Set Write Policy to WriteBack on Adapter 0, VD 3 (target id: 3) success
Learn cycle is active currently

So policy Change to WB will not come into effect immediately

Set Write Policy to WriteBack on Adapter 0, VD 4 (target id: 4) success
Learn cycle is active currently

So policy Change to WB will not come into effect immediately

Set Write Policy to WriteBack on Adapter 0, VD 5 (target id: 5) success
Learn cycle is active currently

So policy Change to WB will not come into effect immediately

Set Write Policy to WriteBack on Adapter 0, VD 6 (target id: 6) success
Learn cycle is active currently

So policy Change to WB will not come into effect immediately

Set Write Policy to WriteBack on Adapter 0, VD 7 (target id: 7) success

Exit Code: 0x00

[[email protected] ~]#/opt/MegaRAID/MegaCli/MegaCli64 -cfgdsply -aall | grep Policy:
Default Cache Policy: WriteBack, ReadAhead, Cached, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAhead, Cached, No Write Cache if Bad BBU
Default Cache Policy: WriteBack, ReadAhead, Cached, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAhead, Cached, No Write Cache if Bad BBU
Default Cache Policy: WriteBack, ReadAhead, Cached, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAhead, Cached, No Write Cache if Bad BBU
Default Cache Policy: WriteBack, ReadAhead, Cached, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAhead, Cached, No Write Cache if Bad BBU
Default Cache Policy: WriteBack, ReadAhead, Cached, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAhead, Cached, No Write Cache if Bad BBU
Default Cache Policy: WriteBack, ReadAhead, Cached, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAhead, Cached, No Write Cache if Bad BBU
Default Cache Policy: WriteBack, ReadAhead, Cached, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAhead, Cached, No Write Cache if Bad BBU
Default Cache Policy: WriteBack, ReadAhead, Cached, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAhead, Cached, No Write Cache if Bad BBU

raid卡进入学习周期。以上是手动执行megacli命令查询到的结果。

lsi megaraid每过一段时间(一般为1个月或3个月)进行放电和充电一次,进行电池校准以延长电池的使用寿命。
每次学习周期时间的长短要看电池充放电的速度,一般几个小时到几十个小时不等。
在学习周期期间raid卡会自动将缓存策略设置为WriteThrough, ReadAhead, Cached, No Write Cache if Bad BBU,并且不能被设置成WriteBack,会导致性能有所下降。

使用lich.node --disk_check --cache 会打印Learn cycle is active
currently,So policy Change to WB will not come into effect
immediately(目前是学习周期,设置可能暂时不会生效)
crontab 中自动执行的 lich.node --disk_check
--cache则会在/opt/mds/log/disk_cache.log中记录Learn cycle is active
currently,So policy Change to WB will not come into effect immediately
使用lich.node --disk_check --json查看时会有一个cache_stat字段 标示为:“Learn” .其它情况暂时标示为“Unknow”

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时间: 2024-08-05 16:48:34

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