[BUG]
When I was testing misc/058, the fs still has around 7GiB free space,
but during that test case, btrfs kernel module reports write failures
and even git commands failed inside that fs.
And obviously the test case failed.
[CAUSE]
It turns out that, the test case itself would require 6GiB (4 data
disks) + 1.5GiB x 2 (the two replace target), thus it requires 9 GiB
free space.
And obviously my partition is not that large and failed.
[FIX]
In fact, we really don't need that much space at all.
The test verifies that two consecutive replace operations can be started
and enqueued, the sleep of 1 second is not strictly necessary as the
first command should start the replace right away.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>