Bug 673455
| Summary: | Capacity and allocation sizes display much bigger than defined in LVM based volumes | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 6 | Reporter: | Min Zhan <mzhan> |
| Component: | libvirt | Assignee: | Osier Yang <jyang> |
| Status: | CLOSED NOTABUG | QA Contact: | Virtualization Bugs <virt-bugs> |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 6.1 | CC: | dallan, dyuan, eblake, jyang, llim, mzhan, xen-maint, yoyzhang |
| Target Milestone: | rc | ||
| Target Release: | --- | ||
| Hardware: | x86_64 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2011-01-28 10:10:25 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
libvirt uses lvcreate to create logical volume, and the command according to above xml "vol.xml" is: /sbin/lvcreate --name vol -L 2097153K /dev/test Tried with above command directly: [root@dhcp ~]# /sbin/lvcreate --name vol2 -L 2097153K /dev/test Rounding up size to full physical extent 2.00 GiB Logical volume "vol2" created lvm> lvdisplay --units k --- Logical volume --- LV Name /dev/test/vol2 VG Name test LV UUID ECr9uN-bVX2-hQLD-c119-e72s-DWvT-QHAMha LV Write Access read/write LV Status available # open 0 LV Size 2101248.00 KiB Current LE 513 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:2 lvm> lvdisplay --- Logical volume --- LV Name /dev/test/vol2 VG Name test LV UUID ECr9uN-bVX2-hQLD-c119-e72s-DWvT-QHAMha LV Write Access read/write LV Status available # open 0 LV Size 2.00 GiB Current LE 513 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:2 So, we pass the correct size to lvcreate, and also gets correct size of the volume, the problem here is "lvcreate" rounds up the size. 2 more examples: --------------------------- [root@dhcp ~]# /sbin/lvcreate --name vol3 -L 2097152K /dev/test Logical volume "vol3" created [root@dhcp ~]# /sbin/lvcreate --name vol4 -L 2097151K /dev/test Rounding up size to full physical extent 2.00 GiB Logical volume "vol4" created And it's resonable for lvcreate doing like so, as if it rounds down the capacity, there will be a bug for lvm (user will fail when trying to write to the volume with the size he specified), just like https://bugzilla.redhat.com/show_bug.cgi?id=670529 for libvirt. Thus, close it as NOTABUG. |
Description of problem: In LVM based storage, create a volume and dump info, found the capacity and allocation values are more bigger than the defined values. Version-Release number of selected component (if applicable): # uname -a Linux dhcp-65-85.nay.redhat.com 2.6.32-99.el6.x86_64 #1 SMP Fri Jan 14 10:46:00 EST 2011 x86_64 x86_64 x86_64 GNU/Linux libvirt-0.8.7-4.el6.x86_64 kernel-2.6.32-99.el6.x86_64 qemu-kvm-0.12.1.2-2.132.el6.x86_64 How reproducible: Always Steps to Reproduce: 1. Create a LVM storage pool # cat test.xml <pool type='logical'> <name>test</name> <source> <name>test</name> <format type='lvm2'/> <device path='/dev/sda5'/> </source> <target> <path>/dev/test</path> </target> </pool> # virsh pool-define test.xml Pool test defined from test.xml # virsh pool-build test Pool test built # virsh pool-start test Pool test started # virsh pool-list Name State Autostart ----------------------------------------- default active yes test active no 2. Create a volume in this storage # cat vol1.xml <volume> <name>vol1</name> <capacity>2147484672</capacity> <allocation>2147484672</allocation> <target> <format type='raw'/> </target> </volume> # virsh vol-create test vol1.xml Vol vol1 created from vol1.xml # virsh vol-dumpxml --pool test vol1 <volume> <name>vol1</name> <key>5IDQQg-Lhfg-z9iA-jau4-I2GF-vuK8-XBSdAG</key> <source> <device path='/dev/sda5'> <extent start='2151677952' end='4303355904'/> </device> </source> <capacity>2151677952</capacity> <allocation>2151677952</allocation> <target> <path>/dev/test/vol1</path> <permissions> <mode>0600</mode> <owner>0</owner> <group>6</group> <label>system_u:object_r:fixed_disk_device_t:s0</label> </permissions> </target> </volume> 3. Some debug info about actual allocated sizes: .... Jan 29 00:15:35 dhcp-65-85 libvirtd: 00:15:35.822: 26681: warning : storageVolumeCreateXML:1301 : voldef->capacity: 2147484672 Jan 29 00:15:35 dhcp-65-85 libvirtd: 00:15:35.822: 26681: warning : virStorageBackendLogicalCreateVol:607 : vol->capacity: 2147484672 Jan 29 00:15:35 dhcp-65-85 libvirtd: 00:15:35.822: 26681: warning : virStorageBackendLogicalCreateVol:612 : capacity: 2097153 .... Actual results: 2151677952 / 1024= 2101248 kb display in volume dumpxml which is much bigger than 2097153 kb. Expected results: The expected result in volume dumpxml should be as debug info: 2147484672 /1024=2097153 kb. Additional info: This bug can also be reproduced with following xml with different size 2147483649. # cat vol.xml <volume> <name>vol</name> <capacity>2147483649</capacity> <allocation>2147483649</allocation> <target> <format type='raw'/> </target> </volume> # virsh vol-create test vol.xml Vol vol created from vol.xml # virsh vol-dumpxml --pool test vol <volume> <name>vol</name> <key>rf2n5V-GkuP-N3p5-ddUQ-21q5-y9TH-dFA6Y0</key> <source> <device path='/dev/sda5'> <extent start='0' end='2151677952'/> </device> </source> <capacity>2151677952</capacity> <allocation>2151677952</allocation> <target> <path>/dev/test/vol</path> <permissions> <mode>0600</mode> <owner>0</owner> <group>6</group> <label>system_u:object_r:fixed_disk_device_t:s0</label> </permissions> </target> </volume>