----- Original Message -----

From: "Reindl Harald" h.reindl@thelounge.net To: "CentOS mailing list" centos@centos.org Cc: "David C. Miller" millerdc@fusion.gat.com Sent: Thursday, April 11, 2013 4:17:18 PM Subject: Re: [CentOS] RAID 6 - opinions

Am 12.04.2013 01:13, schrieb David C. Miller:

...

dd if=/dev/zero of=/backup/5GB.img count=5000 bs=1M 5000+0 records in 5000+0 records out 5242880000 bytes (5.2 GB) copied, 10.8293 s, 484 MB/s

aha, you have 16 GB RAM, write 5 GB to the disk which is easily buffered into RAM and think this measures anything?

do the same with 32 GB instead 5 GB

Good call, I did not even think about that. Here is a 31GB file write.

dd if=/dev/zero of=/backup/30GB.img count=30000 bs=1M 30000+0 records in 30000+0 records out 31457280000 bytes (31 GB) copied, 78.041 s, 403 MB/s

David.