…. Same thing — write-through, battery charging. And the battery backup unit was set to run through auto-learn cycles periodically, which is generally the factory default (these are Dells, with PERC…
Comment: RAID System performance surprises
March 5, 2008 By 7 Comments
… PERC I use OMSA which has Nagios plugins and it works pretty well. Here is the command which tells when next Learn cycle to be: [root@DB01 ~]# omreport storage battery controller=0 Battery 0 on Controller PERC 5/i Integrated (Embedded) Controller PERC 5/i… : Battery 0 State : Ready Recharge Count : Not Applicable Max Recharge Count : Not Applicable Predicted Capacity Status : Ready Learn State : Idle Next Learn Time…
Comment: The perils of uniform hardware and RAID auto-learn cycles
November 16, 2010 By 16 Comments
… with the same PERC controllers. I’ve noticed they fail into WriteThrough mode when the absolute capacity of the battery reaches 25%, so we began alerting on this metric. I’m curious if you recommended the customer disable the learning cycle entirely, or schedule it to run off-peak. I’ve often wondered if the frequency of these cycles has…
