On Wed, Nov 4, 2009 at 11:03, Andrew Dunn <andrew.g.dunn@xxxxxxxxx> wrote: > I sent this a couple days ago, wondering if it fell through the cracks or if I am asking the wrong questions. > > ------ > > I will preface this by saying I only need about 100MB/s out of my array > because I access it via a gigabit crossover cable. > > I am backing up all of my information right now (~4TB) with the > intention of re-creating this array with a larger chunk size and > possibly tweaking the file system a little bit. > > My original array was a raid6 of 9 WD caviar black drives, the chunk > size was 64k. I use USAS-AOC-L8i controllers to address all of my drives > and the TLER setting on the drives is enabled for 7 seconds. > <snip mdadm -D> That array should easily be able to fill your 100MB/s speed requirement. If you really are only accessing over a 1Gib/s link, I wouldn't worry much about tweaking for performance. > > I have noticed slow rebuilding time when I first created the array and > intermittent lockups while writing large data sets. > > Per some reading I was thinking of adjusting my chunk size to 1024k, and > trying to figure out the weird stuff required when creating a file system. > Can you quantify "slow rebuilding time"? And was that just when you first created the array, or do you still see slowness when you check/repair the array? Using a write-intent bitmap might help here. I don't know that any of the options discussed so far are likely to help w/ intermittent lockups. When you see them, are you writing your data over the network? How badly does it lock up your system? What kernel version are you using? Good Luck, -- Conway S. Smith -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
