btrfs/146: make sure hit all stripes in the case of compression

[xfstests-dev.git] / tests / btrfs / 146

diff --git a/tests/btrfs/146 b/tests/btrfs/146
index 7071c128ca0a579cec7bfde7bd359737f3ae3f3c..4d6c5be51a5a376253c15222a20a79c66d4398b2 100755 (executable)
--- a/tests/btrfs/146
+++ b/tests/btrfs/146
@@ -73,10 +73,13 @@ echo "Format and mount"
 _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
+# 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. 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) = 2048K to make sure every stripe can be hit.
 number_of_devices=`echo $SCRATCH_DEV_POOL | wc -w`
-write_kb=$(($number_of_devices * 64))
+write_kb=$(($number_of_devices * 2048))
 _require_fs_space $SCRATCH_MNT $write_kb
 
 testfile=$SCRATCH_MNT/fsync-err-test