From: Matt Benjamin <mbenjamin@redhat.com>
Date: Mon, 13 Feb 2017 01:18:26 +0000 (-0500)
Subject: rgw_file: fix hiwat behavior
X-Git-Tag: v12.0.1~423^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=b8791b2217e9ca87b2d17b51f283fa14bd68b581;p=ceph.git

rgw_file: fix hiwat behavior

Removed logic to skip reclaim processing conditionally on hiwat,
this probably meant to be related to a lowat value, which does
not exist.

Having exercised the hiwat reclaim behavior, noticed that the
path which moves unreachable objects to LRU, could and probably
should remove them altogether when q.size exceeds hiwat.  Now
the max unreachable float is lane hiwat, for all lanes.

Signed-off-by: Matt Benjamin <mbenjamin@redhat.com>
---

diff --git a/src/common/cohort_lru.h b/src/common/cohort_lru.h
index 2c997ff68360..8a8b76699726 100644
--- a/src/common/cohort_lru.h
+++ b/src/common/cohort_lru.h
@@ -131,17 +131,7 @@ namespace cohort {
 	for (int ix = 0; ix < n_lanes; ++ix,
 	       lane_ix = next_evict_lane()) {
 	  Lane& lane = qlane[lane_ix];
-	  /* hiwat check */
-	  /* XXX try the hiwat check unlocked, then recheck locked */
-	  if (lane.q.size() > lane_hiwat) {
-	    lane.lock.lock();
-	    if (lane.q.size() <= lane_hiwat) {
-	      lane.lock.unlock();
-	      continue;
-	    }
-	  } else
-	    continue;
-	  // XXXX if object at LRU has refcnt==1, take it
+	  /* if object at LRU has refcnt==1, it may be reclaimable */
 	  Object* o = &(lane.q.back());
 #if 0 /* XXX save for refactor */
 	  std::cout << __func__
@@ -228,7 +218,12 @@ namespace cohort {
 	    Object::Queue::iterator it =
 	      Object::Queue::s_iterator_to(*o);
 	    lane.q.erase(it);
-	    lane.q.push_back(*o);
+	    /* hiwat check */
+	    if (lane.q.size() > lane_hiwat) {
+	      delete o;
+	    } else {
+	      lane.q.push_back(*o);
+	    }
 	  }
 	  lane.lock.unlock();
 	}