osd/ReplicatedPG: skip promote for DELETE

If an op starts with DELETE there is no need to promote the old content
from the base tier.

Signed-off-by: Sage Weil <sage@inktank.com>

2 files changed, 17 insertions, 0 deletions

diff --git a/src/osd/ReplicatedPG.cc b/src/osd/ReplicatedPG.cc
index ac4d623f1e5..d88bfeb1fa4 100644
--- a/src/osd/ReplicatedPG.cc
+++ b/src/osd/ReplicatedPG.cc
@@ -1219,6 +1219,8 @@ bool ReplicatedPG::maybe_handle_cache(OpRequestRef op, ObjectContextRef obc,
   case pg_pool_t::CACHEMODE_WRITEBACK:
     if (obc.get() && obc->obs.exists) { // we have the object already
       return false;
+    } else if (can_skip_promote(op, obc)) {
+      return false;
     } else { // try and promote!
       promote_object(op, obc);
       return true;
@@ -1247,6 +1249,16 @@ bool ReplicatedPG::maybe_handle_cache(OpRequestRef op, ObjectContextRef obc,
   return false;
 }
 
+bool ReplicatedPG::can_skip_promote(OpRequestRef op, ObjectContextRef obc)
+{
+  MOSDOp *m = static_cast<MOSDOp*>(op->get_req());
+  if (m->ops.empty())
+    return false;
+  if (m->ops[0].op.op == CEPH_OSD_OP_DELETE)
+    return true;
+  return false;
+}
+
 void ReplicatedPG::do_cache_redirect(OpRequestRef op, ObjectContextRef obc)
 {
   MOSDOp *m = static_cast<MOSDOp*>(op->get_req());
diff --git a/src/osd/ReplicatedPG.h b/src/osd/ReplicatedPG.h
index 6b61d8adeaa..67fbd89610e 100644
--- a/src/osd/ReplicatedPG.h
+++ b/src/osd/ReplicatedPG.h
@@ -906,6 +906,11 @@ protected:
    */
   void promote_object(OpRequestRef op, ObjectContextRef obc);
 
+  /**
+   * Check if the op is such that we can skip promote (e.g., DELETE)
+   */
+  bool can_skip_promote(OpRequestRef op, ObjectContextRef obc);
+
   int prepare_transaction(OpContext *ctx);
   
   // pg on-disk content