common: add new config option to defer client eviction

Fixes: https://tracker.ceph.com/issues/58023
Signed-off-by: Dhairya Parmar <dparmar@redhat.com>
(pacific branch has no path src/common/options/mds.yaml.in but
src/common/options.cc; because of this the content has been picked up from
22e4bcf286181ef33b8a09bd8a91ffff218e88ab and added accordingly to
src/common/options.cc)

diff --git a/src/common/options.cc b/src/common/options.cc
index 4dc69cb0db3abff1b06124e50a57fad4becf8e64..06a0815d5a99dc34c577dc6cef6db8a245846713 100644 (file)
--- a/src/common/options.cc
+++ b/src/common/options.cc
@@ -8975,7 +8975,14 @@ std::vector<Option> get_mds_options() {
      .set_default(0)
      .set_flag(Option::FLAG_RUNTIME)
      .set_description("maximum number of entries per directory before new creat/links fail")
-     .set_long_description("The maximum number of entries before any new entries are rejected with ENOSPC.")
+     .set_long_description("The maximum number of entries before any new entries are rejected with ENOSPC."),
+
+    Option("defer_client_eviction_on_laggy_osds", Option::TYPE_BOOL, Option::LEVEL_ADVANCED)
+     .set_default(true)
+     .set_flag(Option::FLAG_RUNTIME)
+     .set_description("Do not evict client if any osd is laggy")
+     .set_long_description("Laggy OSD(s) can make clients laggy or unresponsive, this can lead to their eviction, this option once enabled can help defer client eviction.")
+
   });
 }