ceph-volume: fix fast device alloc size on mulitple device

The size computed by get_physical_fast_allocs() was wrong when the
function had multiple devices to treat.

For instance if there is 4 OSDs and 2 fast devices of each 10G while
allocating 2 slots per fast devvices. The behavior before was that each
slot would be 2.5G meaning that both fast devices would half full. The
behavior now is that each slot will take 5G so that the fast devices
would be full.

Fixes: https://tracker.ceph.com/issues/56031
Signed-off-by: Arthur Outhenin-Chalandre <arthur.outhenin-chalandre@cern.ch>

diff --git a/src/ceph-volume/ceph_volume/devices/lvm/batch.py b/src/ceph-volume/ceph_volume/devices/lvm/batch.py
index 6fa619d5003a280ab69f3a005e849f6eafc3cd3c..afeab60971aa6407bce0a21c6cd20efcddbf1765 100644 (file)
--- a/src/ceph-volume/ceph_volume/devices/lvm/batch.py
+++ b/src/ceph-volume/ceph_volume/devices/lvm/batch.py
@@ -119,14 +119,10 @@ def get_physical_fast_allocs(devices, type_, fast_slots_per_device, new_osds, ar
                 continue
             # any LV present is considered a taken slot
             occupied_slots = len(dev.lvs)
-            # prior to v15.2.8, db/wal deployments were grouping multiple fast devices into single VGs - we need to
-            # multiply requested_slots (per device) by the number of devices in the VG in order to ensure that
-            # abs_size is calculated correctly from vg_size
-            slots_for_vg = len(vg_devices) * requested_slots
             dev_size = dev.vg_size[0]
             # this only looks at the first vg on device, unsure if there is a better
             # way
-            abs_size = disk.Size(b=int(dev_size / slots_for_vg))
+            abs_size = disk.Size(b=int(dev_size / requested_slots))
             free_size = dev.vg_free[0]
             relative_size = int(abs_size) / dev_size
             if requested_size:

diff --git a/src/ceph-volume/ceph_volume/tests/conftest.py b/src/ceph-volume/ceph_volume/tests/conftest.py
index c41a46074439766f5d1a7534e8b156531420f931..a29bb93e18d572310b7a84626b3bd81f1b903433 100644 (file)
--- a/src/ceph-volume/ceph_volume/tests/conftest.py
+++ b/src/ceph-volume/ceph_volume/tests/conftest.py
@@ -58,9 +58,7 @@ def mock_lv_device_generator():
         return dev
     return mock_lv
 
-
-@pytest.fixture
-def mock_devices_available():
+def mock_device():
     dev = create_autospec(device.Device)
     dev.path = '/dev/foo'
     dev.vg_name = 'vg_foo'
@@ -69,21 +67,18 @@ def mock_devices_available():
     dev.available_lvm = True
     dev.vg_size = [21474836480]
     dev.vg_free = dev.vg_size
-    return [dev]
+    dev.lvs = []
+    return dev
+
+@pytest.fixture(params=range(1,3))
+def mock_devices_available(request):
+    ret = []
+    for _ in range(request.param):
+        ret.append(mock_device())
+    return ret
 
 @pytest.fixture
 def mock_device_generator():
-    def mock_device():
-        dev = create_autospec(device.Device)
-        dev.path = '/dev/foo'
-        dev.vg_name = 'vg_foo'
-        dev.lv_name = 'lv_foo'
-        dev.vgs = [lvm.VolumeGroup(vg_name=dev.vg_name, lv_name=dev.lv_name)]
-        dev.available_lvm = True
-        dev.vg_size = [21474836480]
-        dev.vg_free = dev.vg_size
-        dev.lvs = []
-        return dev
     return mock_device
 
 

diff --git a/src/ceph-volume/ceph_volume/tests/devices/lvm/test_batch.py b/src/ceph-volume/ceph_volume/tests/devices/lvm/test_batch.py
index 96a5b5d74db5cc6ffdf9377155cc0ade67110bb7..e1578e33df3a5dbbd4381953730d665906824b5c 100644 (file)
--- a/src/ceph-volume/ceph_volume/tests/devices/lvm/test_batch.py
+++ b/src/ceph-volume/ceph_volume/tests/devices/lvm/test_batch.py
@@ -225,6 +225,16 @@ class TestBatch(object):
                                               'block_db', 2, 2, args)
         assert len(fast) == 2
 
+    def test_get_physical_fast_allocs_abs_size(self, factory,
+                                               conf_ceph_stub,
+                                               mock_devices_available):
+        conf_ceph_stub('[global]\nfsid=asdf-lkjh')
+        args = factory(block_db_slots=None, get_block_db_size=None)
+        fasts = batch.get_physical_fast_allocs(mock_devices_available,
+                                              'block_db', 2, 2, args)
+        for fast, dev in zip(fasts, mock_devices_available):
+            assert fast[2] == int(dev.vg_size[0] / 2)
+
     def test_batch_fast_allocations_one_block_db_length(self, factory, conf_ceph_stub,
                                                   mock_lv_device_generator):
         conf_ceph_stub('[global]\nfsid=asdf-lkjh')