We’ve been noticing since the last Promise firmware that the battery is scheduled to do a reconditioning every other month, on the 1st of that month. May 1st triggered a number of recondition events, starting at 2am and seeming to take about 12 to 24 hours to drain and recharge. When the RAID drains the battery it sets off an alarm, which can be, er, alarming if you’re in the data center. Also, when the hold-time dips the write policy automatically sets to write-thru, which can be changed to Disable Adaptive Write Cache to retain the write-back setting even when the battery drains.
No matter the settings that are used, we’ve found that performance will suffer during a reconditioning event. Therefore, it might make sense to schedule them on weekends, or whenever your organizations requirements allow for reconditioning. However, it is not prudent to outright disable the reconditioning, although it is debatable whether or not 60 day intervals is required for most environments.
