Re: [PATCH 15/32] qemublocktest: Replace 'snapshots' bitmap detection test case data

On 6/15/20 12:10 PM, Peter Krempa wrote: > Use test data which conforms to the new semantics which changed in the > previous patch. Well, a recent patch (the previous patch only touched tests, rather than changing semantics) > > The test data was created by the same set of commands as originally in > commit 0b27b655b1bac480186ce80457113cd5dc34e6a1 > > Signed-off-by: Peter Krempa <pkrempa(a)redhat.com&gt; > --- > tests/qemublocktestdata/bitmap/snapshots.json | 1382 +++++++---------- > tests/qemublocktestdata/bitmap/snapshots.out | 13 +- > 2 files changed, 588 insertions(+), 807 deletions(-) > +++ b/tests/qemublocktestdata/bitmap/snapshots.out > @@ -1,12 +1,17 @@ > libvirt-1-format: > - d: record:0 busy:0 persist:1 inconsist:0 gran:65536 dirty:0 > + d: record:1 busy:0 persist:1 inconsist:0 gran:65536 dirty:0 > + a: record:1 busy:0 persist:1 inconsist:0 gran:65536 dirty:0 > + b: record:1 busy:0 persist:1 inconsist:0 gran:65536 dirty:0 > + c: record:1 busy:0 persist:1 inconsist:0 gran:65536 dirty:0 > current: record:1 busy:0 persist:1 inconsist:0 gran:65536 dirty:0 So, where the old paradigm stitched bitmaps across snapshots (no need to add a bitmap to a new snapshot layer if it was already inactive in the old layer), the new paradigm says that every reachable checkpoint must have an active bitmap in the current layer, in addition to whatever bitmaps it had in earlier layers. Presumably, upcoming patches will tweak libvirt to actually create these bitmaps as part of creating an external snapshot, and I also see how you could utilize qemu adding block-dirty-bitmap-populate as a convenient way for re-creating such bitmaps after the fact (any bitmap that exists in the backing chain should basically mirror the allocation of the current layer in the chain).