pybind/mgr/pg_autoscale: revert to default profile scale-up

pg_autoscale module will now start out all the pools
with a scale-up profile by default.

Added tests in workunits/mon/pg_autoscaler.sh
to evaluate if the default pool creation is
a scale-up profile

Updated documentation and release notes to
reflect the change in the default behavior
of the pg_autoscale profile.

Fixes: https://tracker.ceph.com/issues/53309
Signed-off-by: Kamoltat <ksirivad@redhat.com>
(cherry picked from commit a9f9f7b3fd813d429c4a539edf560d3fb6eb553b)

Conflicts:
	src/pybind/mgr/pg_autoscaler/module.py - trivial fix

diff --git a/PendingReleaseNotes b/PendingReleaseNotes
index 8d8a502666541fa92b4e7610293f47466826036a..4bbf36c37b45e1329788e2efafcfb2819d8eb518 100644 (file)
--- a/PendingReleaseNotes
+++ b/PendingReleaseNotes
@@ -44,9 +44,9 @@
 >=16.2.6
 --------
 
-* MGR: The pg_autoscaler has a new default 'scale-down' profile which provides more
-  performance from the start for new pools (for newly created clusters).
-  Existing clusters will retain the old behavior, now called the 'scale-up' profile.
+* MGR: The pg_autoscaler has a new 'scale-down' profile which provides more
+  performance from the start for new pools. However, the module will remain
+  using it old behavior by default, now called the 'scale-up' profile.
   For more details, see:
 
   https://docs.ceph.com/en/latest/rados/operations/placement-groups/

diff --git a/doc/rados/operations/placement-groups.rst b/doc/rados/operations/placement-groups.rst
index 947fdb1568cb43ff7d621aa0c7e7837211ad93fd..d494f430034a41c82623a939065908fd4cbb2a0b 100644 (file)
--- a/doc/rados/operations/placement-groups.rst
+++ b/doc/rados/operations/placement-groups.rst
@@ -121,24 +121,24 @@ example, a pool that maps to OSDs of class `ssd` and a pool that maps
 to OSDs of class `hdd` will each have optimal PG counts that depend on
 the number of those respective device types.
 
-The autoscaler uses the `scale-down` profile by default, 
-where each pool starts out with a full complements of PGs and only scales 
-down when the usage ratio across the pools is not even. However, it also has 
-a `scale-up` profile, where it starts out each pool with minimal PGs and scales
-up PGs when there is more usage in each pool.
+The autoscaler uses the `scale-up` profile by default,
+where it starts out each pool with minimal PGs and scales
+up PGs when there is more usage in each pool. However, it also has
+a `scale-down` profile, where each pool starts out with a full complements 
+of PGs and only scales down when the usage ratio across the pools is not even.
 
 With only the `scale-down` profile, the autoscaler identifies
 any overlapping roots and prevents the pools with such roots
 from scaling because overlapping roots can cause problems
 with the scaling process.
 
-To use the `scale-up` profile::
+To use the `scale-down` profile::
 
-  ceph osd pool set autoscale-profile scale-up
+  ceph osd pool set autoscale-profile scale-down
 
-To switch back to the default `scale-down` profile::
+To switch back to the default `scale-up` profile::
 
-  ceph osd pool set autoscale-profile scale-down
+  ceph osd pool set autoscale-profile scale-up
 
 Existing clusters will continue to use the `scale-up` profile.
 To use the `scale-down` profile, users will need to set autoscale-profile `scale-down`,

diff --git a/qa/workunits/mon/pg_autoscaler.sh b/qa/workunits/mon/pg_autoscaler.sh
index 3d24b1a6c50c2444379dc600a389a49d3139111f..215b587078f0ca47c7662a9ea4ebd71fc012bb3e 100755 (executable)
--- a/qa/workunits/mon/pg_autoscaler.sh
+++ b/qa/workunits/mon/pg_autoscaler.sh
@@ -45,6 +45,56 @@ ceph osd pool set b pg_autoscale_mode on
 # get num pools again since we created more pools
 NUM_POOLS=$(ceph osd pool ls | wc -l)
 
+# get profiles of pool a and b
+PROFILE1=$(ceph osd pool autoscale-status | grep 'a' | grep -o -m 1 'scale-up\|scale-down' || true)
+PROFILE2=$(ceph osd pool autoscale-status | grep 'b' | grep -o -m 1 'scale-up\|scale-down' || true)
+
+# evaluate the default profile a
+if [[ $PROFILE1 = "scale-up" ]]
+then
+  echo "Success: pool a PROFILE is scale-up"
+else
+  echo "Error: a PROFILE is scale-down"
+  exit 1
+fi
+
+# evaluate the default profile of pool b
+if [[ $PROFILE2 = "scale-up" ]]
+then
+  echo "Success: pool b PROFILE is scale-up"
+else
+  echo "Error: b PROFILE is scale-down"
+  exit 1
+fi
+
+# This part of this code will now evaluate the accuracy of
+# scale-down profile
+
+# change to scale-down profile
+ceph osd pool set autoscale-profile scale-down 
+
+# get profiles of pool a and b
+PROFILE1=$(ceph osd pool autoscale-status | grep 'a' | grep -o -m 1 'scale-up\|scale-down' || true)
+PROFILE2=$(ceph osd pool autoscale-status | grep 'b' | grep -o -m 1 'scale-up\|scale-down' || true)
+
+# evaluate that profile a is now scale-down
+if [[ $PROFILE1 = "scale-down" ]]
+then
+  echo "Success: pool a PROFILE is scale-down"
+else
+  echo "Error: a PROFILE is scale-up"
+  exit 1
+fi
+
+# evaluate the profile of b is now scale-down
+if [[ $PROFILE2 = "scale-down" ]]
+then
+  echo "Success: pool b PROFILE is scale-down"
+else
+  echo "Error: b PROFILE is scale-up"
+  exit 1
+fi
+
 # get pool size
 POOL_SIZE_A=$(ceph osd pool get a size| grep -Eo '[0-9]{1,4}')
 POOL_SIZE_B=$(ceph osd pool get b size| grep -Eo '[0-9]{1,4}')

diff --git a/src/mon/KVMonitor.cc b/src/mon/KVMonitor.cc
index 4d24d727bbe0a25ad78d48ae6dc5a249d2f7e253..defa0e82a7839918bd57bb03ccf70a9f55c8d941 100644 (file)
--- a/src/mon/KVMonitor.cc
+++ b/src/mon/KVMonitor.cc
@@ -48,7 +48,7 @@ void KVMonitor::create_initial()
   version = 0;
   pending.clear();
   bufferlist bl;
-  bl.append("scale-down");
+  bl.append("scale-up");
   pending["config/mgr/mgr/pg_autoscaler/autoscale_profile"] = bl;
 }
 

diff --git a/src/pybind/mgr/pg_autoscaler/module.py b/src/pybind/mgr/pg_autoscaler/module.py
index c57a5feb35dcd067c7f40d4273cd220c638936b3..d3d960cdfb0f48a067b0946294bca61b9eacfa8a 100644 (file)
--- a/src/pybind/mgr/pg_autoscaler/module.py
+++ b/src/pybind/mgr/pg_autoscaler/module.py
@@ -131,11 +131,11 @@ class PgAutoscaler(MgrModule):
             default='scale-up',
             type='str',
             desc='pg_autoscale profiler',
-            long_desc=('Determines the behavior of the autoscaler algorithm '
+            long_desc=('Determines the behavior of the autoscaler algorithm, '
                        '`scale-up` means that it starts out with minmum pgs '
-                       'and scales up when there is pressure, `scale-down` '
-                       'means starts out with full pgs and scales down when '
-                       'there is pressure '),
+                       'and scales up when there is pressure'
+                       '`scale-down means start out with full pgs and scales'
+                       'down when there is pressure'),
             runtime=True),
     ]