Ric Wheeler <rwheeler@xxxxxxxxxx> writes: > The whole thread above is about software MD using commodity drives > (S-ATA or SAS) without battery backed write cache. Yes. However, you mentioned external RAID arrays disable disk caches. That's why I asked if they are using SATA or SCSI/etc. disks, and if they have battery-backed cache. > Also, when you enable the write cache (MD or not) you are buffering > multiple MB's of data that can go away on power loss. Far greater > (10x) the exposure that the partial RAID rewrite case worries about. The cache is flushed with working barriers. I guess it should be superior to disabled WB cache, in both performance and expected disk lifetime. -- Krzysztof Halasa -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
