ReplicatedPG: add osd_recover_clone_overlap_limit to limit cloneswip-5985

We don't want to clone_range from clones too many times.
For now, just skip the cloning if there are too many holes.

Signed-off-by: Samuel Just <sam.just@inktank.com>

2 files changed, 19 insertions, 0 deletions

diff --git a/src/common/config_opts.h b/src/common/config_opts.h
index 52458c268c8..52fc416766b 100644
--- a/src/common/config_opts.h
+++ b/src/common/config_opts.h
@@ -403,6 +403,11 @@ OPTION(osd_op_pq_min_cost, OPT_U64, 65536)
 OPTION(osd_disk_threads, OPT_INT, 1)
 OPTION(osd_recovery_threads, OPT_INT, 1)
 OPTION(osd_recover_clone_overlap, OPT_BOOL, true)   // preserve clone_overlap during recovery/migration
+
+// Only use clone_overlap for recovery if there are fewer than
+// osd_recover_clone_overlap_limit entries in the overlap set
+OPTION(osd_recover_clone_overlap_limit, OPT_INT, 10)
+
 OPTION(osd_backfill_scan_min, OPT_INT, 64)
 OPTION(osd_backfill_scan_max, OPT_INT, 512)
 OPTION(osd_op_thread_timeout, OPT_INT, 15)
diff --git a/src/osd/ReplicatedPG.cc b/src/osd/ReplicatedPG.cc
index ab9c8099a44..eb300792e3a 100644
--- a/src/osd/ReplicatedPG.cc
+++ b/src/osd/ReplicatedPG.cc
@@ -5128,6 +5128,13 @@ void ReplicatedPG::calc_head_subsets(ObjectContext *obc, SnapSet& snapset, const
 	     << " overlap " << prev << dendl;
   }
 
+
+  if (cloning.num_intervals() > g_conf->osd_recover_clone_overlap_limit) {
+    dout(10) << "skipping clone, too many holes" << dendl;
+    clone_subsets.clear();
+    cloning.clear();
+  }
+
   // what's left for us to push?
   data_subset.subtract(cloning);
 
@@ -5197,6 +5204,13 @@ void ReplicatedPG::calc_clone_subsets(SnapSet& snapset, const hobject_t& soid,
     dout(10) << "calc_clone_subsets " << soid << " does not have next " << c
 	     << " overlap " << next << dendl;
   }
+
+  if (cloning.num_intervals() > g_conf->osd_recover_clone_overlap_limit) {
+    dout(10) << "skipping clone, too many holes" << dendl;
+    clone_subsets.clear();
+    cloning.clear();
+  }
+
   
   // what's left for us to push?
   data_subset.subtract(cloning);