Re: [Qemu-devel] qemu drive-mirror to rbd storage : no sparse rbd image
On Wed, 10/08 13:15, Alexandre DERUMIER wrote: Hi, I'm currently planning to migrate our storage to ceph/rbd through qemu drive-mirror and It seem that drive-mirror with rbd block driver, don't create a sparse image. (all zeros are copied to the target rbd). Also note, that it's working fine with qemu-img convert , the rbd volume is sparse after conversion. What is the source format? If the zero clusters are actually unallocated in the source image, drive-mirror will not write those clusters either. I.e. with drive-mirror sync=top, both source and target should have the same qemu-img map output. Fam Could it be related to the bdrv_co_write_zeroes missing features in block/rbd.c ? (It's available in other block drivers (scsi,gluster,raw-aio) , and I don't have this problem with theses block drivers). Regards, Alexandre Derumier -- To unsubscribe from this list: send the line unsubscribe ceph-devel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [Qemu-devel] qemu drive-mirror to rbd storage : no sparse rbd image
What is the source format? If the zero clusters are actually unallocated in the source image, drive-mirror will not write those clusters either. I.e. with drive-mirror sync=top, both source and target should have the same qemu-img map output. Thanks for your reply, I had tried drive mirror (sync=full) with raw file (sparse) - rbd (no sparse) rbd (sparse) - rbd (no sparse) raw file (sparse) - qcow2 on ext4 (sparse) rbd (sparse) - raw on ext4 (sparse) Also I see that I have the same problem with target file format on xfs. raw file (sparse) - qcow2 on xfs (no sparse) rbd (sparse) - raw on xfs (no sparse) I only have this problem with drive-mirror, qemu-img convert seem to simply skip zero blocks. Or maybe this is because I'm using sync=full ? What is the difference between full and top ? sync: what parts of the disk image should be copied to the destination; possibilities include full for all the disk, top for only the sectors allocated in the topmost image. (what is topmost image ?) - Mail original - De: Fam Zheng f...@redhat.com À: Alexandre DERUMIER aderum...@odiso.com Cc: qemu-devel qemu-de...@nongnu.org, Ceph Devel ceph-devel@vger.kernel.org Envoyé: Samedi 11 Octobre 2014 09:01:18 Objet: Re: [Qemu-devel] qemu drive-mirror to rbd storage : no sparse rbd image On Wed, 10/08 13:15, Alexandre DERUMIER wrote: Hi, I'm currently planning to migrate our storage to ceph/rbd through qemu drive-mirror and It seem that drive-mirror with rbd block driver, don't create a sparse image. (all zeros are copied to the target rbd). Also note, that it's working fine with qemu-img convert , the rbd volume is sparse after conversion. What is the source format? If the zero clusters are actually unallocated in the source image, drive-mirror will not write those clusters either. I.e. with drive-mirror sync=top, both source and target should have the same qemu-img map output. Fam Could it be related to the bdrv_co_write_zeroes missing features in block/rbd.c ? (It's available in other block drivers (scsi,gluster,raw-aio) , and I don't have this problem with theses block drivers). Regards, Alexandre Derumier -- To unsubscribe from this list: send the line unsubscribe ceph-devel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [Qemu-devel] qemu drive-mirror to rbd storage : no sparse rbd image
On Sat, 10/11 10:00, Alexandre DERUMIER wrote: What is the source format? If the zero clusters are actually unallocated in the source image, drive-mirror will not write those clusters either. I.e. with drive-mirror sync=top, both source and target should have the same qemu-img map output. Thanks for your reply, I had tried drive mirror (sync=full) with raw file (sparse) - rbd (no sparse) rbd (sparse) - rbd (no sparse) raw file (sparse) - qcow2 on ext4 (sparse) rbd (sparse) - raw on ext4 (sparse) Also I see that I have the same problem with target file format on xfs. raw file (sparse) - qcow2 on xfs (no sparse) rbd (sparse) - raw on xfs (no sparse) These don't tell me much. Maybe it's better to show the actual commands and how you tell sparse from no sparse? Does qcow2 - qcow2 work for you on xfs? I only have this problem with drive-mirror, qemu-img convert seem to simply skip zero blocks. Or maybe this is because I'm using sync=full ? What is the difference between full and top ? sync: what parts of the disk image should be copied to the destination; possibilities include full for all the disk, top for only the sectors allocated in the topmost image. (what is topmost image ?) For sync=top, only the clusters allocated in the image itself is copied; for full, all those clusters allocated in the image itself, and its backing image, and it's backing's backing image, ..., are copied. The image itself, having a backing image or not, is called the topmost image. Fam -- To unsubscribe from this list: send the line unsubscribe ceph-devel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [Qemu-devel] qemu drive-mirror to rbd storage : no sparse rbd image
On Sat, Oct 11, 2014 at 12:25 PM, Fam Zheng f...@redhat.com wrote: On Sat, 10/11 10:00, Alexandre DERUMIER wrote: What is the source format? If the zero clusters are actually unallocated in the source image, drive-mirror will not write those clusters either. I.e. with drive-mirror sync=top, both source and target should have the same qemu-img map output. Thanks for your reply, I had tried drive mirror (sync=full) with raw file (sparse) - rbd (no sparse) rbd (sparse) - rbd (no sparse) raw file (sparse) - qcow2 on ext4 (sparse) rbd (sparse) - raw on ext4 (sparse) Also I see that I have the same problem with target file format on xfs. raw file (sparse) - qcow2 on xfs (no sparse) rbd (sparse) - raw on xfs (no sparse) These don't tell me much. Maybe it's better to show the actual commands and how you tell sparse from no sparse? Does qcow2 - qcow2 work for you on xfs? I only have this problem with drive-mirror, qemu-img convert seem to simply skip zero blocks. Or maybe this is because I'm using sync=full ? What is the difference between full and top ? sync: what parts of the disk image should be copied to the destination; possibilities include full for all the disk, top for only the sectors allocated in the topmost image. (what is topmost image ?) For sync=top, only the clusters allocated in the image itself is copied; for full, all those clusters allocated in the image itself, and its backing image, and it's backing's backing image, ..., are copied. The image itself, having a backing image or not, is called the topmost image. Fam -- Just a wild guess - Alexandre, did you tried detect-zeroes blk option for mirroring targets? -- To unsubscribe from this list: send the line unsubscribe ceph-devel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
RHEL7 source packages
Hi Ceph,
I find this line in https://github.com/ceph/ceph/blob/giant/ceph.spec.in#L382
%if (0%{?rhel} || 0%{?rhel} 7)
odd because it looks like exactly the same as
%if 0%{?rhel}
But it has been added a long time ago
--
Loïc Dachary, Artisan Logiciel Libre
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Re: RHEL7 source packages
[sent mail by mistake, here is the full version ;-]
On 11/10/2014 17:44, Loic Dachary wrote:
Hi Ceph,
I find this line in https://github.com/ceph/ceph/blob/giant/ceph.spec.in#L382
%if (0%{?rhel} || 0%{?rhel} 7)
odd because it looks like exactly the same as
%if 0%{?rhel}
But it has been added a long time ago
I filed a bug to followup http://tracker.ceph.com/issues/9747
Cheers
--
Loïc Dachary, Artisan Logiciel Libre
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NEON / SIMD
Hi Janne, I'd like to learn more about SIMD and NEON. What documents / web site would you recommend to begin ? There are http://projectne10.github.io/Ne10/ http://www.arm.com/products/processors/technologies/neon.php Are you using formal specifications / documentations ? Any hint would be most appreciated :-) Cheers -- Loïc Dachary, Artisan Logiciel Libre signature.asc Description: OpenPGP digital signature
