On 10/04/2011 07:19 PM, Przemek Klosowski wrote:
On 10/03/2011 06:33 PM, Eric Sandeen wrote:
On 10/3/11 5:13 PM, Richard W.M. Jones wrote:
On Mon, Oct 03, 2011 at 04:11:28PM -0500, Eric Sandeen wrote:
testing something more real-world (20T ... 500T?) might still be interesting.
Here's my test script:
qemu-img create -f qcow2 test1.img 500T&& \ guestfish -a test1.img \ memsize 4096 : run : \ part-disk /dev/vda gpt : mkfs ext4 /dev/vda1...
At 100T it doesn't run out of memory, but the man behind the curtain starts to show. The underlying qcow2 file grows to several gigs and I had to kill it. I need to play with the lazy init features of ext4.
Rich.
Bleah. Care to use xfs? ;)
WHy not btrfs? I am testing a 24TB physical server and ext4 creation took forever while btrfs was almost instant. I understand it's still experimental (I hear storing virtual disk images on btrfs still has unresolved performance problems) but vm disk storage should be fine. FWIW I have been using btrfs as my /home at home for some time now; so far so good.
Creating an XFS file system is also a matter of seconds (both xfs and btrfs do dynamic inode allocation).
Note that ext4 has a new feature that allows inodes to be initialized in the background, so you will see much quicker mkfs.ext4 times as well :)
ric