Re: [PATCH v2 1/9] fstests: btrfs: _scratch_mkfs_sized fix min size without mixed option

[Anand Jain <anand.jain@oracle.com>]

On 09/26/2018 02:34 PM, Nikolay Borisov wrote:
> 
> 
> On 26.09.2018 07:07, Anand Jain wrote:
>>
>>
>> On 09/25/2018 06:51 PM, Nikolay Borisov wrote:
>>>
>>>
>>> On 25.09.2018 07:24, Anand Jain wrote:
>>>> As of now _scratch_mkfs_sized() checks if the requested size is below 1G
>>>> and forces the --mixed option for the mkfs.btrfs. Well the correct size
>>>> considering all possible group profiles at which we need to force the
>>>> mixed option is roughly 256Mbytes. So fix that.
>>>>
>>>> Signed-off-by: Anand Jain <anand.jain@oracle.com>
>>>
>>> Have you considered the implications of this w.r.t commit
>>> d4da414a9a9d ("common/rc: raise btrfs mixed mode threshold to 1GB")
>>>
>>> Initially this threshold was 100mb then Omar changed it to 1g. Does this
>>> change affect generic/427?
>>
>> d4da414a9a9d does not explain what was the problem that Omar wanted to
>> address, mainly what was the failure about.
> 
> I just retested on upstream 4.19.0-rc3 with Omar's patch reverted (so
> anything above 100m for fs size is created with non-mixed block groups)
> and the test succeeded. So indeed your change seems to not make a
> difference for this test.

  Thanks for testing.
Anand

>>
>> And no it does not affect. I have verified generic/427 with kernel 4.1
>> and 4.19-rc5 with  btrfs-progs 4.1, 4.9 and latest from kdave they all
>> run fine. Good to integrate.
>>
>> Thanks, Anand
>>
>>>
>>>> ---
>>>>    common/rc | 5 ++++-
>>>>    1 file changed, 4 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/common/rc b/common/rc
>>>> index d5bb1feee2c3..90dc3002bc3d 100644
>>>> --- a/common/rc
>>>> +++ b/common/rc
>>>> @@ -969,7 +969,10 @@ _scratch_mkfs_sized()
>>>>        ;;
>>>>        btrfs)
>>>>        local mixed_opt=
>>>> -    (( fssize <= 1024 * 1024 * 1024 )) && mixed_opt='--mixed'
>>>> +    # minimum size that's needed without the mixed option.
>>>> +    # Ref: btrfs-prog: btrfs_min_dev_size()
>>>> +    # Non mixed mode is also the default option.
>>>> +    (( fssize < $((256 * 1024 *1024)) )) && mixed_opt='--mixed'
>>>>        $MKFS_BTRFS_PROG $MKFS_OPTIONS $mixed_opt -b $fssize $SCRATCH_DEV
>>>>        ;;
>>>>        jfs)
>>>>
>>