1 files changed, 54 insertions, 0 deletions
diff --git a/src/pybind/mgr/cephadm/autotune.py b/src/pybind/mgr/cephadm/autotune.py
new file mode 100644
index 000000000..51c931cba
--- /dev/null
+++ b/src/pybind/mgr/cephadm/autotune.py
@@ -0,0 +1,54 @@
+import logging
+from typing import List, Optional, Callable, Any, Tuple
+
+from orchestrator._interface import DaemonDescription
+
+logger = logging.getLogger(__name__)
+
+
+class MemoryAutotuner(object):
+
+    min_size_by_type = {
+        'mds': 4096 * 1048576,
+        'mgr': 4096 * 1048576,
+        'mon': 1024 * 1048576,
+        'crash': 128 * 1048576,
+        'keepalived': 128 * 1048576,
+        'haproxy': 128 * 1048576,
+    }
+    default_size = 1024 * 1048576
+
+    def __init__(
+            self,
+            daemons: List[DaemonDescription],
+            config_get: Callable[[str, str], Any],
+            total_mem: int,
+    ):
+        self.daemons = daemons
+        self.config_get = config_get
+        self.total_mem = total_mem
+
+    def tune(self) -> Tuple[Optional[int], List[str]]:
+        tuned_osds: List[str] = []
+        total = self.total_mem
+        for d in self.daemons:
+            if d.daemon_type == 'mds':
+                total -= self.config_get(d.name(), 'mds_cache_memory_limit')
+                continue
+            if d.daemon_type != 'osd':
+                assert d.daemon_type
+                total -= max(
+                    self.min_size_by_type.get(d.daemon_type, self.default_size),
+                    d.memory_usage or 0
+                )
+                continue
+            if not self.config_get(d.name(), 'osd_memory_target_autotune'):
+                total -= self.config_get(d.name(), 'osd_memory_target')
+                continue
+            tuned_osds.append(d.name())
+        if total < 0:
+            return None, []
+        if not tuned_osds:
+            return None, []
+        per = total // len(tuned_osds)
+        return int(per), tuned_osds