Hey look at me! I'm top-posting!!! Nanny-nanny-poo-poo Come get me Trolls! You could do the same thing in rescue mode, but this is a destructive operation, which means it'll wipe the current contents of those LVs into the river Styx, so you will need to re-install the OS, so why not do it in install? It will be simpler and more flexible to create your swap area in an LV too then a separate partition, you will also see improvement from the interleaving in swap (if for God's sake you need to see it!). Your not hitting the limits of your PCI bus yet. You are most likely suffering from a poor SATA controller, not all SATA controllers are the same, newer better ones do NCQ tagged command queuing to SATA drives that support it, which allows overlapping IO commands to be issued. Also SATA drives can vary greatly in performance from one model to another from a given manufacturer, so look at the drive specs on the manufacturer's web site. For sequential IO look at sustained data transfer rate. For random IO look at the total read/write seek time. SATA drives typically do 60-70MBs, interleaved you should see 120-140MB/s on sequential. Random IO on SATA usually sucks too badly to even talk about... Cheers, -Ross > -----Original Message----- > From: centos-bounces at centos.org > [mailto:centos-bounces at centos.org] On Behalf Of Russ > Sent: Wednesday, May 09, 2007 11:51 AM > To: CentOS mailing list > Subject: Re: [CentOS] Re: Anaconda doesn't support raid10 > > Ross, > > Thanks for doing the research. Would I not be able to do the > same thing by booting into rescue mode or something and > pre-creating the volumes? > > Also have you noticed a difference between standard and > interleaved set up? In my crude tests with hdparm -t, my > numbers go from about 50 to about 70 on a raid1 to raid10. > > Also intreating to note that with 4 drives in a hardware > raid10 on another box, I was getting upwards of 200mb/s with > similar drives (750gb seagates sata vs 500gb wd sata that I'm > using now). > > Why such a big discreptancy? Is it possible I'm hitting the > limits of the PCI bus? > > Russ > Sent wirelessly via BlackBerry from T-Mobile. > > -----Original Message----- > From: "Ross S. W. Walker" <rwalker at medallion.com> > Date: Wed, 9 May 2007 11:40:42 > To:"CentOS mailing list" <centos at centos.org> > Subject: RE: [CentOS] Re: Anaconda doesn't support raid10 > > > -----Original Message----- > > From: centos-bounces at centos.org > > [mailto:centos-bounces at centos.org] On Behalf Of Ruslan Sivak > > Sent: Wednesday, May 09, 2007 10:36 AM > > To: CentOS mailing list > > Subject: Re: [CentOS] Re: Anaconda doesn't support raid10 > > > > Les Mikesell wrote: > > > Ruslan Sivak wrote: > > > > > >> Yea, I think for these reasons I will use lvm. I have set up a > > >> system as follows: > > >> > > >> /boot raid 1 200mb 4 drives no spares (I guess this makes > > 4 copies of > > >> the data?) > > > > > > What't the point of putting this on more than 2 drives? > > > > > Well for one thing, if 2 drives fail and it doens't get a chance to > > rebuild, then I still have 2 good drives. Another thing is > > if a drive > > fails and the spare is in the wrong location, and the spare > > becomes the > > boot drive, it won't be able to boot, but if all 4 drives are > > copies of > > each other, then everything is well and good. > > >> / 10gb on lvm > > >> /data 50gb on lvm > > >> /backup 250gb on lvm > > >> > > >> rest of space left free to allow for resizing and adding of > > >> partitions with lvm > > >> > > >> I will pull out a drive tommorow and see how resilient > > this is. Does > > >> this sound like a good solution? > > > > > > It is versatile, if you don't know where the additional > > space will be > > > needed but don't think mounting it as separate partitions in > > > subdirectories will be handy. I forgot to mention the > > other reason I > > > like straight RAID1 installs - you can easily clone a > > machine with all > > > of its current software by pulling a drive, booting it in a new > > > machine and rebuilding the raids on both. > > > > > I don't see why I can't pull out 2 drives out of this > install (like 1 > > and 3), put them into another machine and let it rebuild itself. > > I figured out how to create interleaved LVs on the install, it is a > little PITA though. > > Start the install, create all your RAIDs and VGs and LVs as > before, and > move on to the next step, once they have been committed and formatted > before the package installation, reboot and start over. > > Then when you get to the partitioning section, select "Custom" and go > back to that screen. > > Then jump to tty2 (or serial console) and start the shell, go > into lvm, > by typing 'lvm'. > > Within lvm you will need to remove the existing LVs with: > > lvremove <VGname>/<LVname> > > for each LV created, swap, root, etc. > > Then re-create the LVs with: > > lvcreate -L <size in MB>M -i 2 -n <LVname> <VGname> > > Do it for each LV, the -i 2, says interleave (strip) it across 2 PVs. > > Once that's done you can then hit the <Back> button and then go back > in to 'Custom' to have it refresh the setup. Just choose to format > each in their types and move along. > > Remember to choose 'Custom Layout' each time so you don't fubar your > hard work! > > -Ross > > ______________________________________________________________________ > This e-mail, and any attachments thereto, is intended only for use by > the addressee(s) named herein and may contain legally privileged > and/or confidential information. If you are not the intended recipient > of this e-mail, you are hereby notified that any dissemination, > distribution or copying of this e-mail, and any attachments thereto, > is strictly prohibited. If you have received this e-mail in error, > please immediately notify the sender and permanently delete the > original and any copy or printout thereof. > > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos > ______________________________________________________________________ This e-mail, and any attachments thereto, is intended only for use by the addressee(s) named herein and may contain legally privileged and/or confidential information. If you are not the intended recipient of this e-mail, you are hereby notified that any dissemination, distribution or copying of this e-mail, and any attachments thereto, is strictly prohibited. If you have received this e-mail in error, please immediately notify the sender and permanently delete the original and any copy or printout thereof.