73GB disk performance parameters

[Randy Hagedorn]

Hi all,
I am configuring the disk storage for an N4000 system with Jamaica disks being mirrored.

1. Even though the cost per GB is less on one 73GB disk, versus purchasing two 36GB disks, is it better to purchase the two 36GB for better disk I/O throughput?

2. When creating the volume group for 73GB disks, what are the optimal parameters to use for best performance? I was wondering about 'MAX PE per VG' and 'PE Size' and any other configurable parameters.

Thanks,
Randy

[Leif Halvarsson_2]

Hi,

1
Yes, two disks has better performance then one (provided that both disks is in the same volumegroup and data is striped across the disks)

2

For regulary use, the default settings perform well and you will see very little (if any) difference if changing any values.

[Zygmunt Krawczyk]

In your situation the performance issue will be not in disk drives itself, but in SCSI operation mode. Jamaica is designed to support FWD (HVD) and SE disk drives in special disk boxes with some electronics.
What type of disks you plan to install and what type of SCSI controller you have?

Regards,
Zygmunt

[Randy Hagedorn]

Zygmunt,

These Jamaica drives will be used on an N4000 HP-UX system with FW SCSI interfaces. At most there will be 5 drives on each interface card. I don't know the exact model of the drives yet, but I do know that they are Seagate.

Thanks,
Randy