osd,crimson/osd: use pg_committed_to rather than mlcod for submit_transaction

This commit actually changes the bound we're propagating.  This solves
two bugs:
- Using min_last_complete_ondisk caused replicas to be two update rounds
  behind rather than one
- Replicas don't actually have enough information to set
  min_last_complete_ondisk on activation, so we couldn't serve replica
  reads until the first write.  pg_committed_to, on the other hand, is
  fine as the activation last_update cannot become divergent.

Moreover, last_complete won't advance past missing objects causing
min_last_complete_ondisk to be blocked by any replica missing object.
Note that the replica read pathway seperately checks whether the target
is missing locally, so that property was not needed.

Fixes: https://tracker.ceph.com/issues/65086
Fixes: https://tracker.ceph.com/issues/65085
Signed-off-by: Samuel Just <sjust@redhat.com>

diff --git a/src/crimson/osd/ops_executer.cc b/src/crimson/osd/ops_executer.cc
index 7585c96897cc02c3dcb5a2c5412b1acf1690fd73..4e735c3b4cb96c37c0fe958b4f3f563889c86e22 100644 (file)
--- a/src/crimson/osd/ops_executer.cc
+++ b/src/crimson/osd/ops_executer.cc
@@ -828,7 +828,7 @@ void OpsExecuter::fill_op_params(OpsExecuter::modified_by m)
   osd_op_params->mtime = msg->get_mtime();
   osd_op_params->at_version = pg->get_next_version();
   osd_op_params->pg_trim_to = pg->get_pg_trim_to();
-  osd_op_params->pg_committed_to = pg->get_min_last_complete_ondisk();
+  osd_op_params->pg_committed_to = pg->get_pg_committed_to();
   osd_op_params->last_complete = pg->get_info().last_complete;
   osd_op_params->user_modify = (m == modified_by::user);
 }

diff --git a/src/crimson/osd/pg.h b/src/crimson/osd/pg.h
index f37775bc2863142477d750b6faf9391416eb63c8..4c429d6043ab46177118b2dc80265190f9dcf84e 100644 (file)
--- a/src/crimson/osd/pg.h
+++ b/src/crimson/osd/pg.h
@@ -130,7 +130,11 @@ public:
   }
 
   eversion_t get_min_last_complete_ondisk() const {
-    return peering_state.get_min_last_complete_ondisk();
+    return peering_state.get_pg_committed_to();
+  }
+
+  eversion_t get_pg_committed_to() const {
+    return peering_state.get_pg_committed_to();
   }
 
   const pg_info_t& get_info() const final {

diff --git a/src/osd/PeeringState.cc b/src/osd/PeeringState.cc
index 664852a5a5ef6ba4fbe64cc762202344ad754b2d..481581d6affc98ce2afb51d442af8a6b52e3dfe3 100644 (file)
--- a/src/osd/PeeringState.cc
+++ b/src/osd/PeeringState.cc
@@ -2674,6 +2674,10 @@ void PeeringState::activate(
     if (info.last_epoch_started < activation_epoch) {
       info.last_epoch_started = activation_epoch;
       info.last_interval_started = info.history.same_interval_since;
+
+      // updating last_epoch_started ensures that last_update will not
+      // become divergent after activation completes.
+      pg_committed_to = info.last_update;
     }
   }
 

diff --git a/src/osd/PrimaryLogPG.cc b/src/osd/PrimaryLogPG.cc
index 4ee81ccab144049030b271bc20f3de8d96f69c32..be2eddd54790a5e570516056b4af590f79168af7 100644 (file)
--- a/src/osd/PrimaryLogPG.cc
+++ b/src/osd/PrimaryLogPG.cc
@@ -11491,7 +11491,7 @@ void PrimaryLogPG::issue_repop(RepGather *repop, OpContext *ctx)
     ctx->at_version,
     std::move(ctx->op_t),
     recovery_state.get_pg_trim_to(),
-    recovery_state.get_min_last_complete_ondisk(),
+    recovery_state.get_pg_committed_to(),
     std::move(ctx->log),
     ctx->updated_hset_history,
     on_all_commit,