On 10/25/11 2:16 AM, John Doe wrote:
Just wondering how come the array is detected as /dev/sd* instead of the classical /dev/cciss/c0d*... Is the P411 a fake raid?
no, its a seriously fast pci-e SAS2 hardware raid. the physical devices don't show at all. it has 1GB of writeback cache thats backed by flash with a supercap, instead of the traditional battery that dies in 3 years.
I didn't have to install any special drivers to use it, C6 just saw it as-is, /dev/sda is a raid1 of disks 0,1, /dev/sdb is a raid10 of disks 2-22, and sdc is a raid0 of SSD 23,24 (disk 25 is a hot spare for sda,sdb)
its configurable with the hpacucli command tool I got from HP's site.
# lspci -vnn -s 6:0.0 06:00.0 RAID bus controller [0104]: Hewlett-Packard Company Smart Array G6 controllers [103c:323a] (rev 01) Subsystem: Hewlett-Packard Company Smart Array P410 [103c:3243] Flags: bus master, fast devsel, latency 0, IRQ 24 Memory at fbc00000 (64-bit, non-prefetchable) [size=2M] Memory at fbbff000 (64-bit, non-prefetchable) [size=4K] I/O ports at d800 [size=256] Expansion ROM at fbb00000 [disabled] [size=512K] Capabilities: [40] Power Management version 3 Capabilities: [50] MSI: Enable- Count=1/1 Maskable- 64bit+ Capabilities: [70] Express Endpoint, MSI 00 Capabilities: [ac] MSI-X: Enable+ Count=16 Masked- Capabilities: [100] Advanced Error Reporting Kernel driver in use: hpsa Kernel modules: hpsa
# hpacucli ctrl slot=1 show detail
Smart Array P410 in Slot 1 Bus Interface: PCI Slot: 1 Serial Number: PACCRCN810E1R9J Cache Serial Number: PBCDF0CRH0Q13H RAID 6 (ADG) Status: Disabled Controller Status: OK Hardware Revision: Rev C Firmware Version: 5.12 Rebuild Priority: Medium Expand Priority: Medium Surface Scan Delay: 15 secs Surface Scan Mode: Idle Queue Depth: Automatic Monitor and Performance Delay: 60 min Elevator Sort: Enabled Degraded Performance Optimization: Disabled Inconsistency Repair Policy: Disabled Wait for Cache Room: Disabled Surface Analysis Inconsistency Notification: Disabled Post Prompt Timeout: 0 secs Cache Board Present: True Cache Status: OK Accelerator Ratio: 25% Read / 75% Write Drive Write Cache: Disabled Total Cache Size: 1024 MB No-Battery Write Cache: Disabled Cache Backup Power Source: Capacitors Battery/Capacitor Count: 1 Battery/Capacitor Status: OK SATA NCQ Supported: True
dunno if that helps?
since I got it sorted out with 4k blocks and XFS, I'm seeing about 12000 write IOPS via pgbench to that sdb raid10, and 16000 wr/s to the sdc SSD raid1, these are both pretty close to flat out for the disks. sustained writes from iozone hit 1.2GB/sec on sdb and 800MB/s on sdc, also pretty much hardware bandwidth of the disks.