[SOLVED] HP Raid, add GPT with LVM - Perfromance Warning

fireon

Distinguished Member
Oct 25, 2010
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Hello,

i have here an HP Server G8. Two HP Raiddrives: 1x300GB 10K with Raid1 and 6x146GB 15K with Raid10. I've installed the system on Raid1. So i created an GPT Partiontable on the Raid10. But when i create an Partion on it, i get the Waringmessage:

Code:
parted /dev/sdb "mkpart ext4 0s -1s"
Warning: You requested a partition from 0.00B to 440GB.                   
The closest location we can manage is 17.4kB to 440GB.
Is this still acceptable to you?
Yes/No? y
Warning: The resulting partition is not properly aligned for best performance.
Ignore/Cancel?
I read about this is importend for an Hardwareraid.

The last thing should be that:
Code:
parted /dev/sdb set 1 lvm on

Thans for help
Best Regards
 
Last edited:
Found a Solution, hope this is right: http://h10025.www1.hp.com/ewfrf/wc/document?cc=de&lc=de&dlc=de&docname=c03479326

Code:
cat /sys/block/sdb/queue/optimal_io_size 786432cat /sys/block/sdb/queue/minimum_io_size 262144
cat /sys/block/sdb/alignment_offset 0
cat /sys/block/sdb/queue/physical_block_size 512

With the optimal_io_size value 786432 exceeding 1MiB, parted wants to align to the optimal_io_size. 786432 / 512 = 1536 sectors for the optimal size in sectors. The start of a partition should be a multiple of 1536 sectors for optimal performance.

Code:
parted /dev/sdb "mkpart primary 1536s -1s"
Warning: You requested a partition from 786kB to 440GB.                   
The closest location we can manage is 786kB to 440GB.
Is this still acceptable to you?
Yes/No? Yes 
parted /dev/sdb set 1 lvm on                                                         
Information: You may need to update /etc/fstab.

Code:
parted /dev/sdb print
Model: HP LOGICAL VOLUME (scsi)
Disk /dev/sdb: 440GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt


Number  Start  End    Size   File system  Name     Flags
 1      786kB  440GB  440GB               primary  lvm

Best Regards