RE: RAID 5,6 sequential writing seems slower in newer kernels
From: Robert Kierski <hidden>
Date: 2015-12-02 14:15:06
Wow!!! You've stole my thunder. But I can do you one better. I've got DDR3 RAM disks that are capable of sustained performance of about 6G/s each. When combined into a 8+2 RAID6, I get only about 3G/s doing sequential writes, and about 42G/s on reads. CPU is 96.8% idle for the writes. In iostat, I'm seeing about 10x the amount of data going to each individual disk compared to what my user app is writing to the raid device. Bob Kierski Senior Storage Performance Engineer Cray Inc. 380 Jackson Street Suite 210 St. Paul, MN 55101 Tele: 651-967-9590 Fax: 651-605-9001 Cell: 651-890-7461