[PATCH 0/4] Fixes for mkfs.xfs with high amount of CPUs and SSDs

[PATCH 0/4] Fixes for mkfs.xfs with high amount of CPUs and SSDs

[Lukas Herbolt]

Since xfsprogs v6.13.0 mkfs.xfs scales the log size on SSDs with the amount
of CPUs. This leads to various failures from ENOSPC in generic/102 and generic172
(the xfs log can take up to 256MB on 1GB test FS) or depleting the dmthin 
metadata area in generic/347. Downsize of the percentage change is we cannot 
longer check the exact amount of data xfs_io wrote in the generic/102 test.

The xfs/21{6,7} are testing the old behavior before the concurrency option was 
introduced. Forcing the old behavior on newer mkfs.xfs.


Lukas Herbolt (4):
  common/rc:  Add helper to calculate percetage of free space available
  common/xfs: helper function to check if -l/-d/-r concurrecy flags.
  generic/{102,172,347}: Adapt test for XFS on systems with 128+CPUs +
    SSDs
  xfs/216 xfs/217 Use default -l conccurency=0 on mkfs.xfs that supports
    it

 common/rc             |  8 ++++++++
 common/xfs            |  6 ++++++
 tests/generic/102     |  5 +++--
 tests/generic/102.out | 20 ++++++++++----------
 tests/generic/172     |  8 ++++----
 tests/generic/347     |  9 ++++++++-
 tests/xfs/216         |  9 +++++++--
 tests/xfs/217         | 17 +++++++++++++++--
 8 files changed, 61 insertions(+), 21 deletions(-)

-- 
2.53.0

[PATCH 1/4] common/rc: Add helper to calculate percetage of free space available

[Lukas Herbolt]

It calculates percentage of filesystem available space and returns it
in MB. This helper will be used in the following test/generic fixes.

Signed-off-by: Lukas Herbolt <lukas@herbolt.com>
---
 common/rc | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/common/rc b/common/rc
index 5fe44e2158ff..32c566cdb68a 100644
--- a/common/rc
+++ b/common/rc
@@ -6189,6 +6189,14 @@ _require_fanotify_ioerrors()
 	_notrun "$FSTYP does not support fanotify ioerrors"
 }
 
+# Returns percentage of available space on given mount point.
+# usage example:
+# _mb_pct_of_available_space <mount point> <percents>
+#
+_mb_pct_of_available_space()
+{
+        _df_device $1 | $AWK_PROG -v pct=$2 '{printf "%.f", (($5*(pct/100))/1024)}'
+}
 ################################################################################
 # make sure this script returns success
 /bin/true
-- 
2.53.0

Re: [PATCH 1/4] common/rc: Add helper to calculate percetage of free space available

[Darrick J. Wong]

"percentage" in the subject line

On Thu, Apr 30, 2026 at 03:13:16PM +0200, Lukas Herbolt wrote:
> It calculates percentage of filesystem available space and returns it
> in MB. This helper will be used in the following test/generic fixes.
> 
> Signed-off-by: Lukas Herbolt <lukas@herbolt.com>
> ---
>  common/rc | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/common/rc b/common/rc
> index 5fe44e2158ff..32c566cdb68a 100644
> --- a/common/rc
> +++ b/common/rc
> @@ -6189,6 +6189,14 @@ _require_fanotify_ioerrors()
>  	_notrun "$FSTYP does not support fanotify ioerrors"
>  }
>  
> +# Returns percentage of available space on given mount point.

“Computes a percentage of the available space in a filesystem and
returns that quantity in MB.  The percentage must not contain a percent
sign ("%").”

> +# usage example:
> +# _mb_pct_of_available_space <mount point> <percents>

s/percents/percent/

--D

> +#
> +_mb_pct_of_available_space()
> +{
> +        _df_device $1 | $AWK_PROG -v pct=$2 '{printf "%.f", (($5*(pct/100))/1024)}'
> +}
>  ################################################################################
>  # make sure this script returns success
>  /bin/true
> -- 
> 2.53.0
> 
> 

[PATCH 2/4] common/xfs: helper function to check if -l/-d/-r concurrecy flags.

[Lukas Herbolt]

Check if the requested flag is supported by the mkfs.xfs on scratch
device.

Signed-off-by: Lukas Herbolt <lukas@herbolt.com>
---
 common/xfs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/common/xfs b/common/xfs
index f7a6d2f2f03a..12cf6c273c53 100644
--- a/common/xfs
+++ b/common/xfs
@@ -2399,3 +2399,9 @@ _require_xfs_healer()
 	_xfs_healer --supported "$@" &>/dev/null || \
 		_notrun "health monitoring not supported on this kernel"
 }
+
+# Check if -l/-d/-r concurrency is supported.
+_scratch_mkfs_supports_concurrency()
+{
+        _scratch_mkfs_xfs_supported $1 concurrency=0
+}
-- 
2.53.0

Re: [PATCH 2/4] common/xfs: helper function to check if -l/-d/-r concurrecy flags.

[Darrick J. Wong]

On Thu, Apr 30, 2026 at 03:13:18PM +0200, Lukas Herbolt wrote:
> Check if the requested flag is supported by the mkfs.xfs on scratch
> device.
> 
> Signed-off-by: Lukas Herbolt <lukas@herbolt.com>
> ---
>  common/xfs | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/common/xfs b/common/xfs
> index f7a6d2f2f03a..12cf6c273c53 100644
> --- a/common/xfs
> +++ b/common/xfs
> @@ -2399,3 +2399,9 @@ _require_xfs_healer()
>  	_xfs_healer --supported "$@" &>/dev/null || \
>  		_notrun "health monitoring not supported on this kernel"
>  }
> +
> +# Check if -l/-d/-r concurrency is supported.
> +_scratch_mkfs_supports_concurrency()

This is specific to xfs, so I think the name should reflect that.

_scratch_mkfs_xfs_supports_concurrency

> +{
> +        _scratch_mkfs_xfs_supported $1 concurrency=0
> +}

As I noted downthread, -d and -l gained their concurrency= options in
the same release so we probably ought to do future fstests authors a
favor and note that in the comments or just do something dorky like:

_scratch_mkfs_xfs_supports_concurrency()
{
	local arg="${1:-d}"

	# -d and -l gained concurrency options at the same time
	test "$arg" = "-l" && arg="-d"

	_scratch_mkfs_xfs_supported "$arg" concurrency=0
}

--D

> -- 
> 2.53.0
> 
> 

[PATCH 3/4] generic/{102,172,347}: Adapt test for XFS on systems with 128+CPUs + SSDs

[Lukas Herbolt]

XFS will now scale by default its log size according the amount of CPUs. This
can significantly increase the log area and using hardcoded size of file size
will make the test file. Using the the X percent of the free space to create
the file will let the test proceed.

For generic/102 we also have to change the 102.out as we cannot know the
amount written data and it has to be filterred out.

For generic/172 we just use the new function to calculate file big enough
to consume most of the available space.

The generic/347 will use -l concurency=0 in case it is being run on the
XFS filesystem and mkfs.xfs already supports this option.

Signed-off-by: Lukas Herbolt <lukas@herbolt.com>
---
 tests/generic/102     |  5 +++--
 tests/generic/102.out | 20 ++++++++++----------
 tests/generic/172     |  8 ++++----
 tests/generic/347     |  9 ++++++++-
 4 files changed, 25 insertions(+), 17 deletions(-)

diff --git a/tests/generic/102 b/tests/generic/102
index daa5061bd3fe..60e651fefb5b 100755
--- a/tests/generic/102
+++ b/tests/generic/102
@@ -23,12 +23,13 @@ _require_scratch
 dev_size=$((1024 * 1024 * 1024))     # 1GB filesystem
 _scratch_mkfs_sized $dev_size >>$seqres.full 2>&1
 _scratch_mount
+file_size=`_mb_pct_of_available_space $SCRATCH_DEV 95`
 
 for ((i = 0; i < 10; i++)); do
 	echo "loop $i" >>$seqres.full
 
-	$XFS_IO_PROG -f -c "pwrite -b 1m 0 800m" "$SCRATCH_MNT"/file | \
-_filter_xfs_io | _filter_scratch
+	$XFS_IO_PROG -f -c "pwrite -b 1m 0 ${file_size}m" "$SCRATCH_MNT"/file | \
+_filter_xfs_io_numbers | _filter_scratch
 
 	rm -f "$SCRATCH_MNT"/file
 done
diff --git a/tests/generic/102.out b/tests/generic/102.out
index b58aa5ccc68b..647bb23abec1 100644
--- a/tests/generic/102.out
+++ b/tests/generic/102.out
@@ -1,21 +1,21 @@
 QA output created by 102
-wrote 838860800/838860800 bytes at offset 0
+wrote XXXX/XXXX bytes at offset XXXX
 XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
-wrote 838860800/838860800 bytes at offset 0
+wrote XXXX/XXXX bytes at offset XXXX
 XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
-wrote 838860800/838860800 bytes at offset 0
+wrote XXXX/XXXX bytes at offset XXXX
 XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
-wrote 838860800/838860800 bytes at offset 0
+wrote XXXX/XXXX bytes at offset XXXX
 XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
-wrote 838860800/838860800 bytes at offset 0
+wrote XXXX/XXXX bytes at offset XXXX
 XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
-wrote 838860800/838860800 bytes at offset 0
+wrote XXXX/XXXX bytes at offset XXXX
 XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
-wrote 838860800/838860800 bytes at offset 0
+wrote XXXX/XXXX bytes at offset XXXX
 XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
-wrote 838860800/838860800 bytes at offset 0
+wrote XXXX/XXXX bytes at offset XXXX
 XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
-wrote 838860800/838860800 bytes at offset 0
+wrote XXXX/XXXX bytes at offset XXXX
 XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
-wrote 838860800/838860800 bytes at offset 0
+wrote XXXX/XXXX bytes at offset XXXX
 XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
diff --git a/tests/generic/172 b/tests/generic/172
index b67e817b667b..06f9370f065d 100755
--- a/tests/generic/172
+++ b/tests/generic/172
@@ -37,15 +37,15 @@ echo "Reformat with appropriate size"
 blksz="$(_get_block_size $testdir)"
 _scratch_unmount
 
-file_size=$((768 * 1024 * 1024))
 fs_size=$((1024 * 1024 * 1024))
 _scratch_mkfs_sized $fs_size >> $seqres.full 2>&1
 _scratch_mount >> $seqres.full 2>&1
 rm -rf $testdir
 mkdir $testdir
+file_size=`_mb_pct_of_available_space $SCRATCH_DEV 70`
 
 echo "Create a big file and reflink it"
-_pwrite_byte 0x61 0 $file_size $testdir/bigfile >> $seqres.full 2>&1
+_pwrite_byte 0x61 0 ${file_size}m $testdir/bigfile >> $seqres.full 2>&1
 _cp_reflink $testdir/bigfile $testdir/clonefile
 _scratch_sync
 
@@ -54,7 +54,7 @@ _fill_fs $fs_size  $testdir/space $blksz 0 >> $seqres.full 2>&1
 _scratch_sync
 
 echo "CoW the big file"
-out="$(_pwrite_byte 0x62 0 $file_size $testdir/bigfile 2>&1 | \
+out="$(_pwrite_byte 0x62 0 ${file_size}m $testdir/bigfile 2>&1 | \
 	_filter_xfs_io_error)"
 echo ${out} | grep -q "No space left on device" || echo "CoW should have failed with ENOSPC"
 echo ${out} >> $seqres.full 2>&1
@@ -63,7 +63,7 @@ echo ${out}
 echo "Remount and try CoW again"
 _scratch_cycle_mount
 
-out="$(_pwrite_byte 0x62 0 $file_size $testdir/bigfile 2>&1 | \
+out="$(_pwrite_byte 0x62 0 ${file_size}m $testdir/bigfile 2>&1 | \
 	_filter_xfs_io_error)"
 echo ${out} | grep -q "No space left on device" || echo "CoW should have failed with ENOSPC"
 echo ${out} >> $seqres.full 2>&1
diff --git a/tests/generic/347 b/tests/generic/347
index 5c0e3f949585..cf3cfc94c8c4 100755
--- a/tests/generic/347
+++ b/tests/generic/347
@@ -14,6 +14,13 @@ BACKING_SIZE=$((500 * 1024 * 1024 / 512))	# 500M
 VIRTUAL_SIZE=$((10 * $BACKING_SIZE))		# 5000M
 GROW_SIZE=$((100 * 1024 * 1024 / 512))		# 100M
 
+dmthin_mkfs_opts=""
+if [ $FSTYP == "xfs" ]; then
+	if _scratch_mkfs_xfs_supported -l concurrency=0  >> $seqres.full 2>&1; then
+		dmthin_mkfs_opts="-l concurrency=0"
+	fi
+fi
+
 # Override the default cleanup function.
 _cleanup()
 {
@@ -25,7 +32,7 @@ _setup_thin()
 {
 	_dmthin_init $BACKING_SIZE $VIRTUAL_SIZE
 	_dmthin_set_queue
-	_dmthin_mkfs
+	_dmthin_mkfs $dmthin_mkfs_opts
 	_dmthin_mount
 }
 
-- 
2.53.0

Re: [PATCH 3/4] generic/{102,172,347}: Adapt test for XFS on systems with 128+CPUs + SSDs

[Darrick J. Wong]

On Thu, Apr 30, 2026 at 03:13:20PM +0200, Lukas Herbolt wrote:
> XFS will now scale by default its log size according the amount of CPUs. This
> can significantly increase the log area and using hardcoded size of file size
> will make the test file. Using the the X percent of the free space to create
> the file will let the test proceed.
> 
> For generic/102 we also have to change the 102.out as we cannot know the
> amount written data and it has to be filterred out.
> 
> For generic/172 we just use the new function to calculate file big enough
> to consume most of the available space.
> 
> The generic/347 will use -l concurency=0 in case it is being run on the
> XFS filesystem and mkfs.xfs already supports this option.
> 
> Signed-off-by: Lukas Herbolt <lukas@herbolt.com>
> ---
>  tests/generic/102     |  5 +++--
>  tests/generic/102.out | 20 ++++++++++----------
>  tests/generic/172     |  8 ++++----
>  tests/generic/347     |  9 ++++++++-
>  4 files changed, 25 insertions(+), 17 deletions(-)
> 
> diff --git a/tests/generic/102 b/tests/generic/102
> index daa5061bd3fe..60e651fefb5b 100755
> --- a/tests/generic/102
> +++ b/tests/generic/102
> @@ -23,12 +23,13 @@ _require_scratch
>  dev_size=$((1024 * 1024 * 1024))     # 1GB filesystem
>  _scratch_mkfs_sized $dev_size >>$seqres.full 2>&1
>  _scratch_mount
> +file_size=`_mb_pct_of_available_space $SCRATCH_DEV 95`
>  
>  for ((i = 0; i < 10; i++)); do
>  	echo "loop $i" >>$seqres.full
>  
> -	$XFS_IO_PROG -f -c "pwrite -b 1m 0 800m" "$SCRATCH_MNT"/file | \
> -_filter_xfs_io | _filter_scratch
> +	$XFS_IO_PROG -f -c "pwrite -b 1m 0 ${file_size}m" "$SCRATCH_MNT"/file | \
> +_filter_xfs_io_numbers | _filter_scratch

Ah, ok, so we're using 95% of the available space, not just a static
800M?  That's a pretty big difference...

>  	rm -f "$SCRATCH_MNT"/file
>  done
> diff --git a/tests/generic/102.out b/tests/generic/102.out
> index b58aa5ccc68b..647bb23abec1 100644
> --- a/tests/generic/102.out
> +++ b/tests/generic/102.out
> @@ -1,21 +1,21 @@
>  QA output created by 102
> -wrote 838860800/838860800 bytes at offset 0
> +wrote XXXX/XXXX bytes at offset XXXX
>  XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> -wrote 838860800/838860800 bytes at offset 0
> +wrote XXXX/XXXX bytes at offset XXXX
>  XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> -wrote 838860800/838860800 bytes at offset 0
> +wrote XXXX/XXXX bytes at offset XXXX
>  XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> -wrote 838860800/838860800 bytes at offset 0
> +wrote XXXX/XXXX bytes at offset XXXX
>  XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> -wrote 838860800/838860800 bytes at offset 0
> +wrote XXXX/XXXX bytes at offset XXXX
>  XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> -wrote 838860800/838860800 bytes at offset 0
> +wrote XXXX/XXXX bytes at offset XXXX
>  XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> -wrote 838860800/838860800 bytes at offset 0
> +wrote XXXX/XXXX bytes at offset XXXX
>  XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> -wrote 838860800/838860800 bytes at offset 0
> +wrote XXXX/XXXX bytes at offset XXXX
>  XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> -wrote 838860800/838860800 bytes at offset 0
> +wrote XXXX/XXXX bytes at offset XXXX
>  XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> -wrote 838860800/838860800 bytes at offset 0
> +wrote XXXX/XXXX bytes at offset XXXX
>  XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> diff --git a/tests/generic/172 b/tests/generic/172
> index b67e817b667b..06f9370f065d 100755
> --- a/tests/generic/172
> +++ b/tests/generic/172
> @@ -37,15 +37,15 @@ echo "Reformat with appropriate size"
>  blksz="$(_get_block_size $testdir)"
>  _scratch_unmount
>  
> -file_size=$((768 * 1024 * 1024))
>  fs_size=$((1024 * 1024 * 1024))
>  _scratch_mkfs_sized $fs_size >> $seqres.full 2>&1
>  _scratch_mount >> $seqres.full 2>&1
>  rm -rf $testdir
>  mkdir $testdir
> +file_size=`_mb_pct_of_available_space $SCRATCH_DEV 70`

...particularly since you replace 768/1024 with 70% here.

>  echo "Create a big file and reflink it"
> -_pwrite_byte 0x61 0 $file_size $testdir/bigfile >> $seqres.full 2>&1
> +_pwrite_byte 0x61 0 ${file_size}m $testdir/bigfile >> $seqres.full 2>&1
>  _cp_reflink $testdir/bigfile $testdir/clonefile
>  _scratch_sync
>  
> @@ -54,7 +54,7 @@ _fill_fs $fs_size  $testdir/space $blksz 0 >> $seqres.full 2>&1
>  _scratch_sync
>  
>  echo "CoW the big file"
> -out="$(_pwrite_byte 0x62 0 $file_size $testdir/bigfile 2>&1 | \
> +out="$(_pwrite_byte 0x62 0 ${file_size}m $testdir/bigfile 2>&1 | \
>  	_filter_xfs_io_error)"
>  echo ${out} | grep -q "No space left on device" || echo "CoW should have failed with ENOSPC"
>  echo ${out} >> $seqres.full 2>&1
> @@ -63,7 +63,7 @@ echo ${out}
>  echo "Remount and try CoW again"
>  _scratch_cycle_mount
>  
> -out="$(_pwrite_byte 0x62 0 $file_size $testdir/bigfile 2>&1 | \
> +out="$(_pwrite_byte 0x62 0 ${file_size}m $testdir/bigfile 2>&1 | \
>  	_filter_xfs_io_error)"
>  echo ${out} | grep -q "No space left on device" || echo "CoW should have failed with ENOSPC"
>  echo ${out} >> $seqres.full 2>&1
> diff --git a/tests/generic/347 b/tests/generic/347
> index 5c0e3f949585..cf3cfc94c8c4 100755
> --- a/tests/generic/347
> +++ b/tests/generic/347
> @@ -14,6 +14,13 @@ BACKING_SIZE=$((500 * 1024 * 1024 / 512))	# 500M
>  VIRTUAL_SIZE=$((10 * $BACKING_SIZE))		# 5000M
>  GROW_SIZE=$((100 * 1024 * 1024 / 512))		# 100M
>  
> +dmthin_mkfs_opts=""
> +if [ $FSTYP == "xfs" ]; then
> +	if _scratch_mkfs_xfs_supported -l concurrency=0  >> $seqres.full 2>&1; then

_scratch_mkfs_supports_concurrency ?

> +		dmthin_mkfs_opts="-l concurrency=0"
> +	fi
> +fi
> +
>  # Override the default cleanup function.
>  _cleanup()
>  {
> @@ -25,7 +32,7 @@ _setup_thin()
>  {
>  	_dmthin_init $BACKING_SIZE $VIRTUAL_SIZE
>  	_dmthin_set_queue
> -	_dmthin_mkfs
> +	_dmthin_mkfs $dmthin_mkfs_opts
>  	_dmthin_mount
>  }
>  
> -- 
> 2.53.0
> 
> 

[PATCH 4/4] xfs/216 xfs/217 Use default -l conccurency=0 on mkfs.xfs that supports it

[Lukas Herbolt]

The XFS conccurency optimalization breaks the log sizing check on
systems with non-rotational disks and high amount of CPUs. Default to
the old behavior with -l conccurency=0 and with -d concurrency=0.

Signed-off-by: Lukas Herbolt <lukas@herbolt.com>
---
 tests/xfs/216 |  9 +++++++--
 tests/xfs/217 | 17 +++++++++++++++--
 2 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/tests/xfs/216 b/tests/xfs/216
index 091c11d08642..8b4610d5a0a6 100755
--- a/tests/xfs/216
+++ b/tests/xfs/216
@@ -21,14 +21,19 @@ _cleanup()
 }
 
 _require_scratch
-_scratch_mkfs_xfs >/dev/null 2>&1
+if _scratch_mkfs_supports_concurrency -l >> $seqres.full 2>&1; then
+	_scratch_mkfs_xfs -l concurrency=0 >/dev/null 2>&1
+	loop_mkfs_opts="-l concurrency=0"
+else
+	_scratch_mkfs_xfs >/dev/null 2>&1
+	loop_mkfs_opts=
+fi
 _scratch_mount
 
 _require_loop
 LOOP_IMG=$SCRATCH_MNT/test_fs
 LOOP_MNT=$SCRATCH_MNT/test_fs_dir
 
-loop_mkfs_opts=
 $MKFS_XFS_PROG 2>&1 | grep -q rmapbt && \
 	loop_mkfs_opts="$loop_mkfs_opts -m rmapbt=0"
 $MKFS_XFS_PROG 2>&1 | grep -q reflink && \
diff --git a/tests/xfs/217 b/tests/xfs/217
index dae6ce55f475..7c7b33b1ccf7 100755
--- a/tests/xfs/217
+++ b/tests/xfs/217
@@ -20,7 +20,20 @@ _cleanup()
 }
 
 _require_scratch
-_scratch_mkfs_xfs >/dev/null 2>&1
+if _scratch_mkfs_supports_concurrency -l >> $seqres.full 2>&1; then
+	_scratch_mkfs_xfs -l concurrency=0 >/dev/null 2>&1
+	loop_mkfs_opts="-l concurrency=0"
+		if _scratch_mkfs_supports_concurrency -d >> $seqres.full 2>&1; then
+			# We could go just with -l concurency but then on 512CPUs
+			# it gives log size off by one block so better to set
+			# -d concurrency to 0.
+			loop_mkfs_opts="$loop_mkfs_opts -d concurrency=0"
+
+		fi
+else
+	_scratch_mkfs_xfs >/dev/null 2>&1
+	loop_mkfs_opts=
+fi
 _scratch_mount
 # 16T mkfs requires a bit over 2G free
 _require_fs_space $SCRATCH_MNT 2202000
@@ -34,7 +47,7 @@ _do_mkfs()
 	for i in $*; do
 		echo -n "fssize=${i}g "
 		$MKFS_XFS_PROG -f -b size=4096 -l version=2 \
-			-d size=${i}g $loop_dev |grep log
+			-d size=${i}g $loop_dev $loop_mkfs_opts |grep log
 		_mount $loop_dev $LOOP_MNT
 		echo "test write" > $LOOP_MNT/test
 		_unmount $LOOP_MNT > /dev/null 2>&1
-- 
2.53.0

Re: [PATCH 4/4] xfs/216 xfs/217 Use default -l conccurency=0 on mkfs.xfs that supports it

[Darrick J. Wong]

On Thu, Apr 30, 2026 at 03:13:22PM +0200, Lukas Herbolt wrote:
> The XFS conccurency optimalization breaks the log sizing check on

"concurrency optimization"

> systems with non-rotational disks and high amount of CPUs. Default to
> the old behavior with -l conccurency=0 and with -d concurrency=0.

"-l concurrency=0"

> Signed-off-by: Lukas Herbolt <lukas@herbolt.com>
> ---
>  tests/xfs/216 |  9 +++++++--
>  tests/xfs/217 | 17 +++++++++++++++--
>  2 files changed, 22 insertions(+), 4 deletions(-)
> 
> diff --git a/tests/xfs/216 b/tests/xfs/216
> index 091c11d08642..8b4610d5a0a6 100755
> --- a/tests/xfs/216
> +++ b/tests/xfs/216
> @@ -21,14 +21,19 @@ _cleanup()
>  }
>  
>  _require_scratch
> -_scratch_mkfs_xfs >/dev/null 2>&1
> +if _scratch_mkfs_supports_concurrency -l >> $seqres.full 2>&1; then
> +	_scratch_mkfs_xfs -l concurrency=0 >/dev/null 2>&1
> +	loop_mkfs_opts="-l concurrency=0"
> +else
> +	_scratch_mkfs_xfs >/dev/null 2>&1
> +	loop_mkfs_opts=
> +fi
>  _scratch_mount
>  
>  _require_loop
>  LOOP_IMG=$SCRATCH_MNT/test_fs
>  LOOP_MNT=$SCRATCH_MNT/test_fs_dir
>  
> -loop_mkfs_opts=
>  $MKFS_XFS_PROG 2>&1 | grep -q rmapbt && \
>  	loop_mkfs_opts="$loop_mkfs_opts -m rmapbt=0"
>  $MKFS_XFS_PROG 2>&1 | grep -q reflink && \
> diff --git a/tests/xfs/217 b/tests/xfs/217
> index dae6ce55f475..7c7b33b1ccf7 100755
> --- a/tests/xfs/217
> +++ b/tests/xfs/217
> @@ -20,7 +20,20 @@ _cleanup()
>  }
>  
>  _require_scratch
> -_scratch_mkfs_xfs >/dev/null 2>&1
> +if _scratch_mkfs_supports_concurrency -l >> $seqres.full 2>&1; then
> +	_scratch_mkfs_xfs -l concurrency=0 >/dev/null 2>&1

Why does the scratch fs need a -lconcurrency option?

> +	loop_mkfs_opts="-l concurrency=0"
> +		if _scratch_mkfs_supports_concurrency -d >> $seqres.full 2>&1; then
> +			# We could go just with -l concurency but then on 512CPUs
> +			# it gives log size off by one block so better to set
> +			# -d concurrency to 0.
> +			loop_mkfs_opts="$loop_mkfs_opts -d concurrency=0"

concurrency= was added for -d and -l in the same release (6.7) so you
don't have to test them separately.

--D

> +
> +		fi
> +else
> +	_scratch_mkfs_xfs >/dev/null 2>&1
> +	loop_mkfs_opts=
> +fi
>  _scratch_mount
>  # 16T mkfs requires a bit over 2G free
>  _require_fs_space $SCRATCH_MNT 2202000
> @@ -34,7 +47,7 @@ _do_mkfs()
>  	for i in $*; do
>  		echo -n "fssize=${i}g "
>  		$MKFS_XFS_PROG -f -b size=4096 -l version=2 \
> -			-d size=${i}g $loop_dev |grep log
> +			-d size=${i}g $loop_dev $loop_mkfs_opts |grep log
>  		_mount $loop_dev $LOOP_MNT
>  		echo "test write" > $LOOP_MNT/test
>  		_unmount $LOOP_MNT > /dev/null 2>&1
> -- 
> 2.53.0
> 
> 

Re: [PATCH 4/4] xfs/216 xfs/217 Use default -l conccurency=0 on mkfs.xfs that supports it

[Lukas Herbolt]

On 2026-04-30 18:36, Darrick J. Wong wrote:
> On Thu, Apr 30, 2026 at 03:13:22PM +0200, Lukas Herbolt wrote:
>> The XFS conccurency optimalization breaks the log sizing check on
> 
> "concurrency optimization"
> 
>> systems with non-rotational disks and high amount of CPUs. Default to
>> the old behavior with -l conccurency=0 and with -d concurrency=0.
> 
> "-l concurrency=0"
> 
>> Signed-off-by: Lukas Herbolt <lukas@herbolt.com>
>> ---
>>  tests/xfs/216 |  9 +++++++--
>>  tests/xfs/217 | 17 +++++++++++++++--
>>  2 files changed, 22 insertions(+), 4 deletions(-)
>> 
>> diff --git a/tests/xfs/216 b/tests/xfs/216
>> index 091c11d08642..8b4610d5a0a6 100755
>> --- a/tests/xfs/216
>> +++ b/tests/xfs/216
>> @@ -21,14 +21,19 @@ _cleanup()
>>  }
>> 
>>  _require_scratch
>> -_scratch_mkfs_xfs >/dev/null 2>&1
>> +if _scratch_mkfs_supports_concurrency -l >> $seqres.full 2>&1; then
>> +	_scratch_mkfs_xfs -l concurrency=0 >/dev/null 2>&1
>> +	loop_mkfs_opts="-l concurrency=0"
>> +else
>> +	_scratch_mkfs_xfs >/dev/null 2>&1
>> +	loop_mkfs_opts=
>> +fi
>>  _scratch_mount
>> 
>>  _require_loop
>>  LOOP_IMG=$SCRATCH_MNT/test_fs
>>  LOOP_MNT=$SCRATCH_MNT/test_fs_dir
>> 
>> -loop_mkfs_opts=
>>  $MKFS_XFS_PROG 2>&1 | grep -q rmapbt && \
>>  	loop_mkfs_opts="$loop_mkfs_opts -m rmapbt=0"
>>  $MKFS_XFS_PROG 2>&1 | grep -q reflink && \
>> diff --git a/tests/xfs/217 b/tests/xfs/217
>> index dae6ce55f475..7c7b33b1ccf7 100755
>> --- a/tests/xfs/217
>> +++ b/tests/xfs/217
>> @@ -20,7 +20,20 @@ _cleanup()
>>  }
>> 
>>  _require_scratch
>> -_scratch_mkfs_xfs >/dev/null 2>&1
>> +if _scratch_mkfs_supports_concurrency -l >> $seqres.full 2>&1; then
>> +	_scratch_mkfs_xfs -l concurrency=0 >/dev/null 2>&1
> 
> Why does the scratch fs need a -lconcurrency option?
Yeah right it does not need it. Wanted to be sure we do not run into
-ENOSPC but on recommended 10G SCRATCH_DEV we should not.

> 
>> +	loop_mkfs_opts="-l concurrency=0"
>> +		if _scratch_mkfs_supports_concurrency -d >> $seqres.full 2>&1; then
>> +			# We could go just with -l concurency but then on 512CPUs
>> +			# it gives log size off by one block so better to set
>> +			# -d concurrency to 0.
>> +			loop_mkfs_opts="$loop_mkfs_opts -d concurrency=0"
> 
> concurrency= was added for -d and -l in the same release (6.7) so you
> don't have to test them separately.
Just wanted to be sure as those still came in different commits.
> 
> --D
> 
>> +
>> +		fi
>> +else
>> +	_scratch_mkfs_xfs >/dev/null 2>&1
>> +	loop_mkfs_opts=
>> +fi
>>  _scratch_mount
>>  # 16T mkfs requires a bit over 2G free
>>  _require_fs_space $SCRATCH_MNT 2202000
>> @@ -34,7 +47,7 @@ _do_mkfs()
>>  	for i in $*; do
>>  		echo -n "fssize=${i}g "
>>  		$MKFS_XFS_PROG -f -b size=4096 -l version=2 \
>> -			-d size=${i}g $loop_dev |grep log
>> +			-d size=${i}g $loop_dev $loop_mkfs_opts |grep log
>>  		_mount $loop_dev $LOOP_MNT
>>  		echo "test write" > $LOOP_MNT/test
>>  		_unmount $LOOP_MNT > /dev/null 2>&1
>> --
>> 2.53.0
>> 
>> 

-- 
-lhe