> I confirm. Indeed this is weird. Yes. I would try finding out who causes this.
> But how small write could kill WAPBL performances? I don't think it would. However, the amount of filesync writes may still be the problem. The missing data (for me) is how often your WAPBL journal gets flushed (because of these filesync writes). If this happens once a second or even more often, it may completly stall your discs. One filesync write causes one journal flush which causes two disc cache flushes. Additionally, every single small sync write will cause one RAID stripe RMW. How large are your stripes, btw.?
