Re: [zfs-discuss] virtualization, alignment and zfs variation stripes

2009-07-22 Thread Nicolas Williams
On Wed, Jul 22, 2009 at 02:45:52PM -0500, Bob Friesenhahn wrote: > On Wed, 22 Jul 2009, t. johnson wrote: > >Lets say I have a simple-ish setup that uses vmware files for > >virtual disks on an NFS share from zfs. I'm wondering how zfs' > >variable block size comes into play? Does it make the ali

Re: [zfs-discuss] virtualization, alignment and zfs variation stripes

2009-07-22 Thread Fajar A. Nugraha
On Thu, Jul 23, 2009 at 12:29 PM, thomas wrote: > Hmm.. I guess that's what I've heard as well. > > I do run compression and believe a lot of others would as well. So then, it > seems > to me that if I have guests that run a filesystem formatted with 4k blocks for > example.. I'm inevitably going

Re: [zfs-discuss] virtualization, alignment and zfs variation stripes

2009-07-22 Thread thomas
Hmm.. I guess that's what I've heard as well. I do run compression and believe a lot of others would as well. So then, it seems to me that if I have guests that run a filesystem formatted with 4k blocks for example.. I'm inevitably going to have this overlap when using ZFS network storage? So if

Re: [zfs-discuss] virtualization, alignment and zfs variation stripes

2009-07-22 Thread Bob Friesenhahn
On Wed, 22 Jul 2009, t. johnson wrote: Lets say I have a simple-ish setup that uses vmware files for virtual disks on an NFS share from zfs. I'm wondering how zfs' variable block size comes into play? Does it make the alignment problem go away? Does it make it worse? Or should we perhaps be

[zfs-discuss] virtualization, alignment and zfs variation stripes

2009-07-22 Thread t. johnson
One of the things that commonly comes up in the server virtualization world is making sure that all of the storage elements are "aligned". This is because there are often so many levels of abstraction each using their own "block size" that without any tuning, they'll usually overlap and can cau