Bug 1570156
| Summary: | Creating a VDO volume with --sparseIndex enabled results in an index on-disk size matching that of a dense index | |||
|---|---|---|---|---|
| Product: | Red Hat Enterprise Linux 7 | Reporter: | Bryan Gurney <bgurney> | |
| Component: | vdo | Assignee: | Sweet Tea Dorminy <sweettea> | |
| Status: | CLOSED ERRATA | QA Contact: | Jakub Krysl <jkrysl> | |
| Severity: | unspecified | Docs Contact: | ||
| Priority: | high | |||
| Version: | 7.5 | CC: | awalsh, jkrysl, limershe, rhandlin | |
| Target Milestone: | rc | Keywords: | ZStream | |
| Target Release: | --- | |||
| Hardware: | Unspecified | |||
| OS: | Unspecified | |||
| Whiteboard: | ||||
| Fixed In Version: | 6.1.1.79 | Doc Type: | If docs needed, set a value | |
| Doc Text: | Story Points: | --- | ||
| Clone Of: | ||||
| : | 1572496 (view as bug list) | Environment: | ||
| Last Closed: | 2018-10-30 09:39:31 UTC | Type: | Bug | |
| Regression: | --- | Mount Type: | --- | |
| Documentation: | --- | CRM: | ||
| Verified Versions: | Category: | --- | ||
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | ||
| Cloudforms Team: | --- | Target Upstream Version: | ||
| Embargoed: | ||||
| Bug Depends On: | ||||
| Bug Blocks: | 1572496 | |||
Tested on:
RHEL-7.6-20180626.0
kernel-3.10.0-915.el7
kmod-vdo-6.1.1.99-1.el7
vdo-6.1.1.99-2.el7
# vdo create --name vdo --device /dev/sdb
Creating VDO vdo
Starting VDO vdo
Starting compression on VDO vdo
VDO instance 109 volume is ready at /dev/mapper/vdo
# vdo status --name vdo | grep 'Index sparse'
Index sparse: disabled
# hexdump -C /dev/sdb -n 4K
00000000 64 6d 76 64 6f 30 30 31 05 00 00 00 04 00 00 00 |dmvdo001........|
00000010 00 00 00 00 5d 00 00 00 00 00 00 00 09 01 02 00 |....]...........|
00000020 c5 ac 79 38 18 70 05 00 a3 c1 39 51 1e 12 44 0d |..y8.p....9Q..D.|
00000030 a7 4a 8c a4 93 44 bd 9a 00 00 00 00 01 00 00 00 |.J...D..........|
00000040 00 00 00 00 01 00 00 00 d8 5c 0a 00 00 00 00 00 |.........\......|
00000050 00 ff ff ff 00 00 00 00 00 dc 64 0f 61 00 00 00 |..........d.a...|
00000060 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
*
00001000
0x0a5cd8 * 4096 = 2781708288
# vdo create --name vdo --device /dev/sdb --sparseIndex enabled
Creating VDO vdo
Starting VDO vdo
Starting compression on VDO vdo
VDO instance 110 volume is ready at /dev/mapper/vdo
# vdo status --name vdo | grep 'Index sparse'
Index sparse: enabled
# hexdump -C /dev/sdb -n 4K
00000000 64 6d 76 64 6f 30 30 31 05 00 00 00 04 00 00 00 |dmvdo001........|
00000010 00 00 00 00 5d 00 00 00 00 00 00 00 09 01 02 00 |....]...........|
00000020 19 0c ce 40 18 70 05 00 7d 53 cd c9 6f c6 42 6f |...@.p..}S..o.Bo|
00000030 96 d5 62 34 d0 5d b3 47 00 00 00 00 01 00 00 00 |..b4.].G........|
00000040 00 00 00 00 01 00 00 00 2c d7 58 00 00 00 00 00 |........,.X.....|
00000050 00 ff ff ff 00 00 00 00 01 fb 19 c1 7f 00 00 00 |................|
00000060 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
*
00001000
0x58d72c * 4096 = 23847944192
23847944192 / 2781708288 = 8.57
So the sparse index on disk is roughly 8.57x bigger than dense index.
Regression testing passed.
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHBA-2018:3094 |
Description of problem: When creating a VDO volume with default options, a UDS index using 0.25 GB of memory is created, which uses about 2.6 GB of disk space: # vdo create --name=vdo1 --device=/dev/nvme0n1p1 --verbose Creating VDO vdo1 grep MemAvailable /proc/meminfo pvcreate -qq --test /dev/nvme0n1p1 modprobe kvdo vdoformat --uds-checkpoint-frequency=0 --uds-memory-size=0.25 /dev/nvme0n1p1 vdodumpconfig /dev/nvme0n1p1 Starting VDO vdo1 dmsetup status vdo1 grep MemAvailable /proc/meminfo modprobe kvdo vdodumpconfig /dev/nvme0n1p1 dmsetup create vdo1 --uuid VDO-bee917e8-cc33-4c59-8943-623eebac2b1b --table '0 200940480 vdo /dev/nvme0n1p1 4096 disabled 0 32768 16380 on auto vdo1 ack=1,bio=4,bioRotationInterval=64,cpu=2,hash=1,logical=1,physical=1' dmsetup status vdo1 Starting compression on VDO vdo1 dmsetup message vdo1 0 compression on dmsetup status vdo1 VDO instance 11 volume is ready at /dev/mapper/vdo1 # vdo status | grep Index Index checkpoint frequency: 0 Index memory setting: 0.25 Index parallel factor: 0 Index sparse: disabled Index status: online # cat /sys/uds/index/12/name dev=/dev/nvme0n1p1 offset=4096 size=2781704192 # hexdump -C -n 4096 /dev/nvme0n1p1 00000000 64 6d 76 64 6f 30 30 31 05 00 00 00 04 00 00 00 |dmvdo001........| 00000010 00 00 00 00 5d 00 00 00 00 00 00 00 09 01 02 00 |....]...........| 00000020 bb 7d 8a 70 4b 6a 05 00 be e9 17 e8 cc 33 4c 59 |.}.pKj.......3LY| 00000030 89 43 62 3e eb ac 2b 1b 00 00 00 00 01 00 00 00 |.Cb>..+.........| 00000040 00 00 00 00 01 00 00 00 d8 5c 0a 00 00 00 00 00 |.........\......| 00000050 00 ff ff ff 00 00 00 00 00 68 2e d4 e7 00 00 00 |.........h......| 00000060 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| * 00001000 If the user attempts to create a VDO volume with default options, except adding "--sparseIndex=enabled" to create a sparse index. This should result in about 25 GB of disk space being used for the index, but it doesn't; instead it seems to show the same "size=2781704192" string in the /sys/uds "name", which suggests the on-disk index is about 2.6 GB in size. # vdo create --name=vdo1 --device=/dev/nvme0n1p1 --sparseIndex=enabled --verbose Creating VDO vdo1 grep MemAvailable /proc/meminfo pvcreate -qq --test /dev/nvme0n1p1 modprobe kvdo vdoformat --uds-checkpoint-frequency=0 --uds-memory-size=0.25 --uds-sparse /dev/nvme0n1p1 vdodumpconfig /dev/nvme0n1p1 Starting VDO vdo1 dmsetup status vdo1 grep MemAvailable /proc/meminfo modprobe kvdo vdodumpconfig /dev/nvme0n1p1 dmsetup create vdo1 --uuid VDO-8b6dc126-f9dc-4898-9e68-cfe58ae8cf34 --table '0 200940480 vdo /dev/nvme0n1p1 4096 disabled 0 32768 16380 on auto vdo1 ack=1,bio=4,bioRotationInterval=64,cpu=2,hash=1,logical=1,physical=1' dmsetup status vdo1 Starting compression on VDO vdo1 dmsetup message vdo1 0 compression on dmsetup status vdo1 VDO instance 12 volume is ready at /dev/mapper/vdo1 # vdo status | grep Index Index checkpoint frequency: 0 Index memory setting: 0.25 Index parallel factor: 0 Index sparse: enabled Index status: online # cat /sys/uds/index/13/name dev=/dev/nvme0n1p1 offset=4096 size=2781704192 # hexdump -C -n 4096 /dev/nvme0n1p1 00000000 64 6d 76 64 6f 30 30 31 05 00 00 00 04 00 00 00 |dmvdo001........| 00000010 00 00 00 00 5d 00 00 00 00 00 00 00 09 01 02 00 |....]...........| 00000020 84 ad 82 73 4b 6a 05 00 8b 6d c1 26 f9 dc 48 98 |...sKj...m.&..H.| 00000030 9e 68 cf e5 8a e8 cf 34 00 00 00 00 01 00 00 00 |.h.....4........| 00000040 00 00 00 00 01 00 00 00 d8 5c 0a 00 00 00 00 00 |.........\......| 00000050 00 ff ff ff 00 00 00 00 00 3d 47 39 ab 00 00 00 |.........=G9....| 00000060 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| * 00001000 Version-Release number of selected component (if applicable): vdo-6.1.0.149-16.x86_64 How reproducible: 100% Steps to Reproduce: 1. Create a VDO volume with the command "vdo create --name=vdo1 --device=<blockdevice> --sparseIndex=enabled" to try to create a VDO volume with a dense index. Run "hexdump -C -n 4096 <blockdevice>" to dump the contents of the geometry block. Run "vdo status", and save the output. Remove this VDO volume. 2. Create a VDO volume with the command "vdo create --name=vdo1 --device=<blockdevice>" to try to create a VDO volume with a dense index. Run "hexdump -C -n 4096 <blockdevice>" to dump the contents of the geometry block. Run "vdo status", and save the output. Remove this VDO volume. 3. Compare the values in 0x48 to 0x4f of the geometry block; they should not be equal. Actual results: The values in 0x48 to 0x4f of the geometry block are equal. Expected results: The values in 0x48 to 0x4f of the geometry block are not equal (and the integer there is about 10 times larger). Additional info: