Merge pull request ceph#51656 from amathuria/wip-amat-mclock-change-default-scrub-cost

osd: Change scrub cost in case of mClock scheduler

Author: ljflores

src/common/options/global.yaml.in

@@ -3645,6 +3645,12 @@ options:
   desc: Cost for scrub operations in work queue
   default: 50_M
   with_legacy: true
+- name: osd_scrub_event_cost
+  type: size
+  level: advanced
+  desc: Cost for each scrub operation, used when osd_op_queue=mclock_scheduler
+  default: 4_K
+  with_legacy: true
 # set requested scrub priority higher than scrub priority to make the
 # requested scrubs jump the queue of scheduled scrubs
 - name: osd_requested_scrub_priority

src/osd/OSD.cc

@@ -1756,9 +1756,8 @@ void OSDService::queue_scrub_event_msg(PG* pg,
   auto msg = new MSG_TYPE(pg->get_pgid(), epoch, act_token);
   dout(15) << "queue a scrub event (" << *msg << ") for " << *pg
            << ". Epoch: " << epoch << " token: " << act_token << dendl;
-
   enqueue_back(OpSchedulerItem(
-    unique_ptr<OpSchedulerItem::OpQueueable>(msg), cct->_conf->osd_scrub_cost,
+    unique_ptr<OpSchedulerItem::OpQueueable>(msg), get_scrub_cost(),
     pg->scrub_requeue_priority(with_priority, qu_priority), ceph_clock_now(), 0, epoch));
 }
 
@@ -1769,12 +1768,22 @@ void OSDService::queue_scrub_event_msg(PG* pg,
   const auto epoch = pg->get_osdmap_epoch();
   auto msg = new MSG_TYPE(pg->get_pgid(), epoch);
   dout(15) << "queue a scrub event (" << *msg << ") for " << *pg << ". Epoch: " << epoch << dendl;
-
   enqueue_back(OpSchedulerItem(
-    unique_ptr<OpSchedulerItem::OpQueueable>(msg), cct->_conf->osd_scrub_cost,
+    unique_ptr<OpSchedulerItem::OpQueueable>(msg), get_scrub_cost(),
     pg->scrub_requeue_priority(with_priority), ceph_clock_now(), 0, epoch));
 }
 
+int64_t OSDService::get_scrub_cost()
+{
+
+  int64_t cost_for_queue = cct->_conf->osd_scrub_cost;
+  if (cct->_conf->osd_op_queue == "mclock_scheduler") {
+    cost_for_queue = cct->_conf->osd_scrub_event_cost *
+                     cct->_conf->osd_shallow_scrub_chunk_max;
+  }
+  return cost_for_queue;
+}
+
 void OSDService::queue_for_scrub(PG* pg, Scrub::scrub_prio_t with_priority)
 {
   queue_scrub_event_msg<PGScrub>(pg, with_priority);

src/osd/OSD.h

@@ -601,6 +601,7 @@ class OSDService : public Scrub::ScrubSchedListener {
   /// provided by the executing scrub (i.e. taken from PgScrubber::m_flags)
   template <class MSG_TYPE>
   void queue_scrub_event_msg(PG* pg, Scrub::scrub_prio_t with_priority);
+  int64_t get_scrub_cost();
 
   utime_t defer_recovery_until;
   uint64_t recovery_ops_active;

src/osd/scheduler/mClockScheduler.h

@@ -33,7 +33,7 @@
 
 namespace ceph::osd::scheduler {
 
-constexpr double default_min = 1.0;
+constexpr double default_min = 0.0;
 constexpr double default_max = std::numeric_limits<double>::is_iec559 ?
   std::numeric_limits<double>::infinity() :
   std::numeric_limits<double>::max();