Have you tried the option no_wdelay with sync? Perhaps that's what you want since it minimizes the cache effect. 2011/4/14 Sylar Shen <kimulaaa@xxxxxxxxx>: > Yes, after testing I found that "sync" will still do the cache in memory. > But what I want to know Âis the real speed to write data into the disks. > I know it may not be safe without using memory and the speed may go very slow. > However, that's what I am trying to find out. > Thanks~~^^ > -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html