[PATCH v2] fstests: btrfs/146: make sure hit all stripes in the case of compression

[PATCH v2] fstests: btrfs/146: make sure hit all stripes in the case of compression

[Lu Fengqi]

In the case of compression, each 128K input data chunk will be compressed
to 4K (because of the characters written are duplicate). Therefore we have
to write (128K * 16) to make sure every stripe can be hit.

Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
---

V2: Modify the regular expression to ensure that it matches various
compress mount options.

 tests/btrfs/146 | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/tests/btrfs/146 b/tests/btrfs/146
index 7071c128ca0a..a51eda68eaf3 100755
--- a/tests/btrfs/146
+++ b/tests/btrfs/146
@@ -74,9 +74,16 @@ _scratch_pool_mkfs "-d raid0 -m raid1" > $seqres.full 2>&1
 _scratch_mount
 
 # How much do we need to write? We need to hit all of the stripes. btrfs uses
-# a fixed 64k stripesize, so write enough to hit each one
+# a fixed 64k stripesize, so write enough to hit each one. In the case of
+# compression, each 128K input data chunk will be compressed to 4K (because of
+# the characters written are duplicate). Therefore we have to write (128K * 16)
+# to make sure every stripe can be hit.
 number_of_devices=`echo $SCRATCH_DEV_POOL | wc -w`
-write_kb=$(($number_of_devices * 64))
+if ! echo $MOUNT_OPTIONS | grep -qoP 'compress(-force)?(=(?!no)|,|$)'; then
+	write_kb=$(($number_of_devices * 64))
+else
+	write_kb=$(($number_of_devices * 2048))
+fi
 _require_fs_space $SCRATCH_MNT $write_kb
 
 testfile=$SCRATCH_MNT/fsync-err-test
-- 
2.16.2

Re: [PATCH v2] fstests: btrfs/146: make sure hit all stripes in the case of compression

[Eryu Guan]

On Thu, Mar 08, 2018 at 01:56:45PM +0800, Lu Fengqi wrote:
> In the case of compression, each 128K input data chunk will be compressed
> to 4K (because of the characters written are duplicate). Therefore we have
> to write (128K * 16) to make sure every stripe can be hit.
> 
> Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
> ---
> 
> V2: Modify the regular expression to ensure that it matches various
> compress mount options.
> 
>  tests/btrfs/146 | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/tests/btrfs/146 b/tests/btrfs/146
> index 7071c128ca0a..a51eda68eaf3 100755
> --- a/tests/btrfs/146
> +++ b/tests/btrfs/146
> @@ -74,9 +74,16 @@ _scratch_pool_mkfs "-d raid0 -m raid1" > $seqres.full 2>&1
>  _scratch_mount
>  
>  # How much do we need to write? We need to hit all of the stripes. btrfs uses
> -# a fixed 64k stripesize, so write enough to hit each one
> +# a fixed 64k stripesize, so write enough to hit each one. In the case of
> +# compression, each 128K input data chunk will be compressed to 4K (because of
> +# the characters written are duplicate). Therefore we have to write (128K * 16)
> +# to make sure every stripe can be hit.
>  number_of_devices=`echo $SCRATCH_DEV_POOL | wc -w`
> -write_kb=$(($number_of_devices * 64))
> +if ! echo $MOUNT_OPTIONS | grep -qoP 'compress(-force)?(=(?!no)|,|$)'; then

I'm wondering if we could just write ($number_of_devices * 2048)K data
unconditionally, so we could get rid of this case switch and the fancy
perl style regexp?

Thanks,
Eryu

> +	write_kb=$(($number_of_devices * 64))
> +else
> +	write_kb=$(($number_of_devices * 2048))
> +fi
>  _require_fs_space $SCRATCH_MNT $write_kb
>  
>  testfile=$SCRATCH_MNT/fsync-err-test
> -- 
> 2.16.2
> 
> 
> 
> --
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> the body of a message to majordomo@vger.kernel.org
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Re: [PATCH v2] fstests: btrfs/146: make sure hit all stripes in the case of compression

[Lu Fengqi]

On Thu, Mar 08, 2018 at 02:10:59PM +0800, Eryu Guan wrote:
>On Thu, Mar 08, 2018 at 01:56:45PM +0800, Lu Fengqi wrote:
>> In the case of compression, each 128K input data chunk will be compressed
>> to 4K (because of the characters written are duplicate). Therefore we have
>> to write (128K * 16) to make sure every stripe can be hit.
>> 
>> Signed-off-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
>> ---
>> 
>> V2: Modify the regular expression to ensure that it matches various
>> compress mount options.
>> 
>>  tests/btrfs/146 | 11 +++++++++--
>>  1 file changed, 9 insertions(+), 2 deletions(-)
>> 
>> diff --git a/tests/btrfs/146 b/tests/btrfs/146
>> index 7071c128ca0a..a51eda68eaf3 100755
>> --- a/tests/btrfs/146
>> +++ b/tests/btrfs/146
>> @@ -74,9 +74,16 @@ _scratch_pool_mkfs "-d raid0 -m raid1" > $seqres.full 2>&1
>>  _scratch_mount
>>  
>>  # How much do we need to write? We need to hit all of the stripes. btrfs uses
>> -# a fixed 64k stripesize, so write enough to hit each one
>> +# a fixed 64k stripesize, so write enough to hit each one. In the case of
>> +# compression, each 128K input data chunk will be compressed to 4K (because of
>> +# the characters written are duplicate). Therefore we have to write (128K * 16)
>> +# to make sure every stripe can be hit.
>>  number_of_devices=`echo $SCRATCH_DEV_POOL | wc -w`
>> -write_kb=$(($number_of_devices * 64))
>> +if ! echo $MOUNT_OPTIONS | grep -qoP 'compress(-force)?(=(?!no)|,|$)'; then
>
>I'm wondering if we could just write ($number_of_devices * 2048)K data
>unconditionally, so we could get rid of this case switch and the fancy
>perl style regexp?

That is exactly what I want. I'm just not sure if anyone will mind that the
amount of data written is not exactly hitting all stripes. Since you think
it does not matter, I'm glad to delete it.

>
>Thanks,
>Eryu
>
>> +	write_kb=$(($number_of_devices * 64))
>> +else
>> +	write_kb=$(($number_of_devices * 2048))
>> +fi
>>  _require_fs_space $SCRATCH_MNT $write_kb
>>  
>>  testfile=$SCRATCH_MNT/fsync-err-test
>> -- 
>> 2.16.2
>> 
>> 
>> 
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>
>

-- 
Thanks,
Lu