2009/1/5 David Lethe <david@xxxxxxxxxxxx>: >> -----Original Message----- >> From: linux-raid-owner@xxxxxxxxxxxxxxx [mailto:linux-raid- >> owner@xxxxxxxxxxxxxxx] On Behalf Of hank peng >> Sent: Sunday, January 04, 2009 7:08 PM >> To: linux-raid >> Subject: Are there some alignment settings when creating filesystem on >> RAID5 array which can improve performance? >> >> Hi, everybody: >> I have a machine and centos 5.2 installed on it. I have created a >> RAID5 array with five SATA disks, then I create LVM on this array. >> #pvcreate /dev/md0 >> #vgcreate myvg /dev/md0 >> #lvcreate -n mylv myvg >> As you see, I want to use XFS or ReiserFS on "mylv" volume. I wonder >> if there are some alignment settings when creating such file systems >> so that a better R/W performance can be achieved. Thx in advance. >> >> >> -- >> The simplest is not all best but the best is surely the simplest! >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-raid" >> in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > > Yes, but be specific. How do you use the volume? Do you want to optimize for IOPs or > raw file transfer? What is mix of random vs sequential for both reads and writes. > What is block/chunk size of volume, raidset, filesystem? Reveal your > journaling settings. What are you getting now, and how did you measure it? Are things > like NCQ/TCQ/read-write cache enabled or disabled? > > How are the disks physically attached? PCI(-X) or PCIe, how many channels are you using, or are > the disks attached via USB ports. > I am new to this area, so I'm not quite familiar with some words what you mentioned. The machine has a SATA controller (chip is Marvell 6081) attached on PCI-X bus. Five SATA II disks are attached to it. Each disk has 500G space. The following is my procedure: #mdadm -C /dev/md0 -l5 -n5 /dev/sd{a,b,c,d,e} After recovery is done, I do this: #pvcreate /dev/md0 #vgcreate myvg /dev/md0 #lvcreate -n mylv -L 1000G myvg #mkfs.xfs /dev/myvg/mylv or #mkfs.reiserfs /dev/myvg/mylv mount this file system and begin to use it. I mainly want to optimise its sequential write performace, IOPs is not my concern. SATA driver is provided by marvell, so NCQ/TCQ/read-write is default. > Need more info. > > > -- The simplest is not all best but the best is surely the simplest! -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
