Re: [Qemu-devel] Some uncertain about implementing stream optimized writing

2011-06-29 Thread Fam Zheng
On Wed, Jun 29, 2011 at 4:15 PM, Kevin Wolf wrote: > Am 29.06.2011 06:47, schrieb Fam Zheng: >> Hi, >> >> I have implemented reading for sparse optimized and come to implement >> writing. It is a little complicated and I am not sure what is the best >> approach. Could you give me some advice? >> >

Re: [Qemu-devel] Some uncertain about implementing stream optimized writing

2011-06-29 Thread Kevin Wolf
Am 29.06.2011 06:47, schrieb Fam Zheng: > Hi, > > I have implemented reading for sparse optimized and come to implement > writing. It is a little complicated and I am not sure what is the best > approach. Could you give me some advice? > > Here is the details: (pasted from http://warm.la/soc/?p=9

Re: [Qemu-devel] Some uncertain about implementing stream optimized writing

2011-06-29 Thread Stefan Hajnoczi
On Wed, Jun 29, 2011 at 7:18 AM, Fam Zheng wrote: > No error report with writing (dd of=/dev/sda ...), but can't change > data, (dd if=/dev/sda) dump unchanged. I suggest we return EIO on non-allocating writes. That way the user will know there is a problem with what they are trying to do. qemu-

Re: [Qemu-devel] Some uncertain about implementing stream optimized writing

2011-06-28 Thread Fam Zheng
No error report with writing (dd of=/dev/sda ...), but can't change data, (dd if=/dev/sda) dump unchanged. On Wed, Jun 29, 2011 at 1:47 PM, Stefan Hajnoczi wrote: > On Wed, Jun 29, 2011 at 5:47 AM, Fam Zheng wrote: >> Stream optimized VMDK image allocates minimized space for a compressed >> clus

Re: [Qemu-devel] Some uncertain about implementing stream optimized writing

2011-06-28 Thread Stefan Hajnoczi
On Wed, Jun 29, 2011 at 5:47 AM, Fam Zheng wrote: > Stream optimized VMDK image allocates minimized space for a compressed > cluster, which means if there is high compress ratio, a cluster > possibly only takes one physical sector in the file. It makes > overwriting hard, especially when new data

[Qemu-devel] Some uncertain about implementing stream optimized writing

2011-06-28 Thread Fam Zheng
Hi, I have implemented reading for sparse optimized and come to implement writing. It is a little complicated and I am not sure what is the best approach. Could you give me some advice? Here is the details: (pasted from http://warm.la/soc/?p=98) Stream optimized VMDK image allocates minimized sp