thrasher: improve documentation a little

Signed-off-by: Greg Farnum <gregory.farnum@dreamhost.com>

diff --git a/teuthology/task/thrashosds.py b/teuthology/task/thrashosds.py
index 83be97bbcef33927e67dc8552259fbb8bc221f97..feb82f13b2c002b781f8e13d8d339895241e5321 100644 (file)
--- a/teuthology/task/thrashosds.py
+++ b/teuthology/task/thrashosds.py
@@ -8,9 +8,12 @@ log = logging.getLogger(__name__)
 def task(ctx, config):
     """
     "Thrash" the OSDs by randomly marking them out/down (and then back
-    in) until the task is ended.
-
+    in) until the task is ended. This loops, and every opDelay seconds it
+    randomly chooses to add or remove an OSD (even odds) unless there are
+    fewer than minOut OSDs out of the cluster, or more than minIn OSDs in
+    the cluster.
     All commands are run on mon0 and it stops when __exit__ is called.
+
     The config is optional, and is a dict containing some or all of:
     minIn: (default 2) the minimum number of OSDs to keep in the cluster
     minOut: (default 0) the minimum number of OSDs to keep out of the cluster