Hello, first af all I''m sorry for my bad english, I''m italian. I need an advice on configuring xen, this is my first xen install. I have a server HP Proliant DL 580G5 16G ram and 8 SAS disks, 2 of 70Gb and tha last 6 of 140Gb.. First I configure my raid controller: I do a raid1 with the two 70Gb disks and a raid5 with the last 5 with a spare disk. Then I install my dom0, a debian etch amd64 on raid1, 67G for / and 3G for swap. The raid5 5 disks are a single partition with LVM. Now I want to to create my virtual machines. Dom1: an oracle and mysql server with a web server, dom2: another oracle, mysql and web server, clone of dom1 for tests purposes and a dom3 for development. I like debian so the operating system wil be debian etch amd64 for all the virtual machines. How much ram can I assign to every dom? And how much swap space? Can I later change the amount of ram assigned to every dom in case I need to create new ones? _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
2008/11/13 Robert Dunkley <Robert@saq.co.uk>> Hi Mauro, > > > > You would need to partition the arrays in LVM if you needed more VMs. In > the end it comes down to convenience versus performance, individual Raid 1s > perform best when multiple VMs come under load but one large Raid array is > easier to manage. >ok, thanks anche scuse me if I reply directly to you, I forget to do a reply-all. Last thing...do you suggest only raid1 stripes instead of raid1+0? Because my controller give me raid5 and raid1+0 choices. I have a Smart Array P400 SAS/SATA Controller in a HP Proliant DL 580 G5.>_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Hi Mauro, My experience with VMs and raid configs is the best array type varies depending on the VMs use, just as it does with normal physical servers. Web and Db the two uses you mention are typically more reliant on random read and write performance rather than sequential read or write performance. In your setup if two VMs start to come under typical heavy disk load for Web and DB servers then it is likely two raid 1 arrays (1 for each VM) will perform better than a single Raid 10 or Raid 5. I''d be interested to hear what others think. Rob From: Mauro [mailto:mrsanna1@gmail.com] Sent: 13 November 2008 08:47 To: Robert Dunkley Cc: xen-users@lists.xensource.com Subject: Re: [Xen-users] new on xen. 2008/11/13 Robert Dunkley <Robert@saq.co.uk> Hi Mauro, You would need to partition the arrays in LVM if you needed more VMs. In the end it comes down to convenience versus performance, individual Raid 1s perform best when multiple VMs come under load but one large Raid array is easier to manage. ok, thanks anche scuse me if I reply directly to you, I forget to do a reply-all. Last thing...do you suggest only raid1 stripes instead of raid1+0? Because my controller give me raid5 and raid1+0 choices. I have a Smart Array P400 SAS/SATA Controller in a HP Proliant DL 580 G5. The SAQ Group Registered Office: 18 Chapel Street, Petersfield, Hampshire GU32 3DZ SEMTEC Limited Trading as SAQ is Registered in England & Wales Company Number: 06481952 http://www.saqnet.co.uk AS29219 SAQ Group Delivers high quality, honestly priced communication and I.T. services to UK Business. DSL : Domains : Email : Hosting : CoLo : Servers : Racks : Transit : Backups : Managed Networks : Remote Support. Find us in http://www.thebestof.co.uk/petersfield _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users