[Bugs] [Bug 1220173] SEEK_HOLE support (optimization)

[bugzilla at redhat.com]

https://bugzilla.redhat.com/show_bug.cgi?id=1220173



--- Comment #42 from Deepak C Shetty <dshetty at redhat.com> ---
(In reply to Christopher Pereira from comment #1)
> Besides not using SEEK_HOLE/SEEK_DATA to optimize disk IO, I also discovered
> that GB of zeros are send through the network. That hurts.
> 
> To reproduce:
> 
> - mount a remote gluster volume
> - cp a sparse image from the mounted volume to /tmp

cp doesn't understand qcow2 format, but if we use qemu-nbd to create a 
local block device (say /dev/nbdX) thats backed by .qcow2 file, then
dd (with or without conv=sparse) might work ? I m curious to know. Have you
tried this already ?

thanx,
deepak

-- 
You are receiving this mail because:
You are on the CC list for the bug.
You are the assignee for the bug.