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Diffstat (limited to 'results/classifier/108/debug/1330')
| -rw-r--r-- | results/classifier/108/debug/1330 | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/results/classifier/108/debug/1330 b/results/classifier/108/debug/1330 new file mode 100644 index 000000000..c6e8cec79 --- /dev/null +++ b/results/classifier/108/debug/1330 @@ -0,0 +1,197 @@ +debug: 0.934 +other: 0.932 +permissions: 0.930 +vnc: 0.925 +graphic: 0.923 +device: 0.921 +performance: 0.917 +semantic: 0.911 +files: 0.909 +PID: 0.908 +socket: 0.908 +KVM: 0.886 +boot: 0.871 +network: 0.868 + +qemu-img finishes successfully while having errors in commit or bitmaps operations +Description of problem: +Problem raises when trying to merge two images with the top image almost +full, and base image having stale bitmaps (bitmaps missing from +the top image). +In our usercase, the size of the LV that contains the base image is not +accounting for the stale bitmaps, and therefore, when we run `commit` or +`bitmap --merge`, it fails with: +``` +qcow2_free_clusters failed: No space left on device +qemu-img: Lost persistent bitmaps during inactivation of node '#block308': Failed to write bitmap 'stale-bitmap-002' to file: No space left on device +qemu-img: Failed to flush the refcount block cache: No space left on device +``` +However, in both cases `qemu-img` returned successfully, +while having logs printed to `stderr`, and failing the merge. + +For commit operation, the data was commited successfully, it failed as it +was adding the bitmaps. +Still, the process exit with success. + +On the other hand, for bitmaps operation, since its main purpose is to +manipulate bitmaps, and it failed, it should not return with code 0. +The process shall return with error code. +Also, bitmaps in the base image are left with the `in-use` flag set. +Steps to reproduce: +1. Create these lvs and chown them to the user +``` +sudo lvcreate --name base.qcow2 --size 128m storage +sudo chown $USER:$USER /dev/mapper/storage-base.qcow2 +sudo lvcreate --name top.qcow2 --size 128m storage +sudo chown $USER:$USER /dev/mapper/storage-top.qcow2 +``` +2. Run this python script. Note the `STALE_BITMAPS` counter. Using 6, 11, or 13 stale + bitmaps, the `commit`, or the `bitmaps` operations shall fail. +``` +# Reproduce ENOSPC error when merging into base image with lot of bitmaps. + +import json +import subprocess + +IMG_SIZE = 1 << 30 +LV_SIZE = 128 << 20 + +# Testing shows that we can merge successfully with 13 bitmaps, and require +# size calculation is more strict, allowing up to 11 bitamps. +STALE_BITMAPS = 11 + +def run(*cmd): + subprocess.run(cmd, check=True) + +def output(cmd): + cp = subprocess.run(cmd, stdout=subprocess.PIPE, check=True) + return json.loads(cp.stdout) + +def info(img): + return output(["qemu-img", "info", "--output", "json", img]) + +def measure(img): + return output(["qemu-img", "measure", "-f", "qcow2", "-O", "qcow2", "--output", "json", img]) + +def check(img): + cmd = ["qemu-img", "check", "-f", "qcow2", "--output", "json", img] + cp = subprocess.run(cmd, stdout=subprocess.PIPE) + if cp.returncode not in (0, 3): + raise RuntimeError(f"Check failed") + + return json.loads(cp.stdout) + +def indent(info): + return json.dumps(info, indent=2) + +base = "/dev/mapper/storage-base.qcow2" +top = "/dev/mapper/storage-top.qcow2" + +# Start with clean lvs by discarding current data. +run("blkdiscard", base) +run("blkdiscard", top) + +print("Creating base") +run("qemu-img", "create", "-f", "qcow2", base, str(IMG_SIZE)) + +# Simulate stale bitmaps - missing in top. +for i in range(STALE_BITMAPS): + bitmap = f"stale-bitmap-{i:03d}" + print(f"Creating stale bitmap {bitmap}") + run("qemu-img", "bitmap", "--add", base, bitmap) + +print("Info base before merge") +base_info = info(base) +print(indent(base_info)) + +print("Check base before merge") +base_check = check(base) +print(indent(base_check)) + +print("Measure base before merge") +base_measure = measure(base) +print(indent(base_measure)) + +print("Creating top") +run("qemu-img", "create", "-f", "qcow2", "-b", base, "-F", "qcow2", top) + +print("Adding good bitmap to top") +run("qemu-img", "bitmap", "--add", top, "good-bitmap") + +print("Writing data to top") +cmd = f"write -P {ord('B')} 0 126m" +run("qemu-io", "-f", "qcow2", "-c", cmd, top) + +print("Info top before merge") +top_info = info(top) +print(indent(top_info)) + +print("Check top before merge") +top_check = check(top) +print(indent(top_check)) + +print("Measure top before merge") +top_measure = measure(top) +print(indent(top_measure)) + +print("Commit top into base") +run("qemu-img", "commit", "-f", "qcow2", "-t", "none", "-b", base, "-d", "-p", top) + +print("Add good bitmap to base") +run("qemu-img", "bitmap", "--add", base, "good-bitmap") + +print("Merge good bitmap from top to base") +run("qemu-img", "bitmap", "--merge", "good-bitmap", "-F", "qcow2", "-b", top, base, "good-bitmap") + +print("Info base after merge") +print(indent(info(base))) + +print("Check base after merge") +print(indent(check(base))) + +print("Measure base after merge") +print(indent(measure(base))) +``` +Additional information: +Example output of the script with 6 stale bitmaps: +``` +Commit top into base + (100.00/100%) +Image committed. +Add good bitmap to base +Merge good bitmap from top to base +qcow2_free_clusters failed: No space left on device +qemu-img: Lost persistent bitmaps during inactivation of node '#block159': Failed to write bitmap 'good-bitmap' to file: No space left on device +qemu-img: Failed to flush the refcount block cache: No space left on device +Info base after merge +{ + "virtual-size": 1073741824, + "filename": "/dev/mapper/storage-base.qcow2", + "cluster-size": 65536, + "format": "qcow2", + "actual-size": 0, + "format-specific": { + "type": "qcow2", + "data": { + "compat": "1.1", + "compression-type": "zlib", + "lazy-refcounts": false, + "bitmaps": [ + ... + { + "flags": [ + "in-use", + "auto" + ], + "name": "good-bitmap", + "granularity": 65536 + } + ], + "refcount-bits": 16, + "corrupt": false, + "extended-l2": false + } + }, + "dirty-flag": false +} +``` |