| Message ID | 20170531130820.17634-6-jlayton@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, May 31, 2017 at 09:08:20AM -0400, Jeff Layton wrote: > With btrfs, we can't really put the log on a separate device. What we > can do however is mirror the metadata across two devices and make the > data striped across all devices. When we turn on dmerror then the > metadata can fall back to using the other mirror while the data errors > out. > > Note that the current incarnation of btrfs has a fixed 64k stripe > width. If that ever changes or becomes settable, we may need to adjust > the amount of data that the test program writes. > > Signed-off-by: Jeff Layton <jlayton@redhat.com> > --- > common/rc | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/common/rc b/common/rc > index 83765aacfb06..078270451b53 100644 > --- a/common/rc > +++ b/common/rc > @@ -830,6 +830,8 @@ _scratch_mkfs() > ;; > btrfs) > mkfs_cmd="$MKFS_BTRFS_PROG" > + [ "$USE_EXTERNAL" = yes -a ! -z "$SCRATCH_LOGDEV" ] && \ > + mkfs_cmd="$mkfs_cmd -d raid0 -m raid1 $SCRATCH_LOGDEV" I don't think this is the correct way to do it. If btrfs doesn't support external log device, then this test doesn't fit btrfs, or we need other ways to test btrfs. One of the problems of this hack is that raid1 requires all devices are in the same size, we have a _require_scratch_dev_pool_equal_size() rule to check on it, but this hack doesn't do the proper check and test fails if SCRATCH_LOGDEV is smaller or bigger in size. If btrfs "-d raid0 -m raid1" is capable to do this writeback error test, perhaps you can write a new btrfs test and mkfs with "-d raid0 -m raid1" explicitly. e.g. ... _require_scratch_dev_pool 2 _require_scratch_dev_pool_equal_size ... _scratch_mkfs "-d raid0 -m raid1" ... Thanks, Eryu > mkfs_filter="cat" > ;; > ext3) > -- > 2.9.4 > > -- > To unsubscribe from this list: send the line "unsubscribe fstests" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, 2017-06-06 at 17:19 +0800, Eryu Guan wrote: > On Wed, May 31, 2017 at 09:08:20AM -0400, Jeff Layton wrote: > > With btrfs, we can't really put the log on a separate device. What we > > can do however is mirror the metadata across two devices and make the > > data striped across all devices. When we turn on dmerror then the > > metadata can fall back to using the other mirror while the data errors > > out. > > > > Note that the current incarnation of btrfs has a fixed 64k stripe > > width. If that ever changes or becomes settable, we may need to adjust > > the amount of data that the test program writes. > > > > Signed-off-by: Jeff Layton <jlayton@redhat.com> > > --- > > common/rc | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/common/rc b/common/rc > > index 83765aacfb06..078270451b53 100644 > > --- a/common/rc > > +++ b/common/rc > > @@ -830,6 +830,8 @@ _scratch_mkfs() > > ;; > > btrfs) > > mkfs_cmd="$MKFS_BTRFS_PROG" > > + [ "$USE_EXTERNAL" = yes -a ! -z "$SCRATCH_LOGDEV" ] && \ > > + mkfs_cmd="$mkfs_cmd -d raid0 -m raid1 $SCRATCH_LOGDEV" > > I don't think this is the correct way to do it. If btrfs doesn't support > external log device, then this test doesn't fit btrfs, or we need other > ways to test btrfs. > > One of the problems of this hack is that raid1 requires all devices are > in the same size, we have a _require_scratch_dev_pool_equal_size() rule > to check on it, but this hack doesn't do the proper check and test fails > if SCRATCH_LOGDEV is smaller or bigger in size. > > If btrfs "-d raid0 -m raid1" is capable to do this writeback error test, > perhaps you can write a new btrfs test and mkfs with "-d raid0 -m raid1" > explicitly. e.g. > > ... > _require_scratch_dev_pool 2 > _require_scratch_dev_pool_equal_size > ... > _scratch_mkfs "-d raid0 -m raid1" > ... > > Thanks, > Eryu Yeah, that's probably the right way to do this. It looks like btrfs also has $SCRATCH_DEV_POOL, and we can probably base it on that. I'll look at reworking it.
diff --git a/common/rc b/common/rc index 83765aacfb06..078270451b53 100644 --- a/common/rc +++ b/common/rc @@ -830,6 +830,8 @@ _scratch_mkfs() ;; btrfs) mkfs_cmd="$MKFS_BTRFS_PROG" + [ "$USE_EXTERNAL" = yes -a ! -z "$SCRATCH_LOGDEV" ] && \ + mkfs_cmd="$mkfs_cmd -d raid0 -m raid1 $SCRATCH_LOGDEV" mkfs_filter="cat" ;; ext3)
With btrfs, we can't really put the log on a separate device. What we can do however is mirror the metadata across two devices and make the data striped across all devices. When we turn on dmerror then the metadata can fall back to using the other mirror while the data errors out. Note that the current incarnation of btrfs has a fixed 64k stripe width. If that ever changes or becomes settable, we may need to adjust the amount of data that the test program writes. Signed-off-by: Jeff Layton <jlayton@redhat.com> --- common/rc | 2 ++ 1 file changed, 2 insertions(+)