On 9/29/20 11:55 AM, Filipe Manana wrote:
On Tue, Sep 29, 2020 at 4:50 PM Anand Jain <anand.jain@xxxxxxxxxx> wrote:
btrfs/064 aimed to test balance and replace concurrency while the stress
test is running in the background.
However, as the balance and the replace operation are mutually
exclusive, so they can never run concurrently.
And it's good to have a test that verifies that attempting to run them
concurrently doesn't cause any problems, like crashes, memory leaks or
some sort of filesystem corruption.
For example btrfs/187, which I wrote sometime ago, tests that running
send, balance and deduplication in parallel doesn't result in crashes,
since in the past they were allowed to run concurrently.
I see no point in removing the test, it's useful.
My confusion was around whether this test was actually testing what we
think it should be testing. If this test was meant to make sure that
replace works while we've got load on the fs, then clearly it's not
doing what we think it's doing.
In this case if we're ok with it exercising the exclusion path then I
think we at least need to update the comment at the beginning of the
test so it's clear what the purpose of the test is. And then we need to
make sure we do actually have a test where device replace is properly
exercised. I _think_ it is with btrfs/065 and some others, so just
updating the comment here would be enough. Thanks,
Josef
