From: Sage Weil <sage@redhat.com>
Date: Fri, 7 Sep 2018 21:05:01 +0000 (-0500)
Subject: osd: avoid dropping osd_lock when pg osdmaps are not laggy
X-Git-Tag: v14.0.1~211^2~5
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=33f4f22193b79384c1fdd6cd7731d5c0a30bbb31;p=ceph.git

osd: avoid dropping osd_lock when pg osdmaps are not laggy

We only need to drop the lock if we are going to block.

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

diff --git a/src/osd/OSD.cc b/src/osd/OSD.cc
index 57f6d9fa0631..80163edabe6b 100644
--- a/src/osd/OSD.cc
+++ b/src/osd/OSD.cc
@@ -7448,7 +7448,15 @@ void OSD::handle_osd_map(MOSDMap *m)
     epoch_t max_lag = cct->_conf->osd_map_cache_size *
       m_osd_pg_epoch_max_lag_factor;
     ceph_assert(max_lag > 0);
-    if (osdmap->get_epoch() > max_lag) {
+    epoch_t osd_min = 0;
+    for (auto shard : shards) {
+      epoch_t min = shard->get_min_pg_epoch();
+      if (osd_min == 0 || min < osd_min) {
+	osd_min = min;
+      }
+    }
+    if (osdmap->get_epoch() > max_lag &&
+	osdmap->get_epoch() - max_lag > osd_min) {
       epoch_t need = osdmap->get_epoch() - max_lag;
       dout(10) << __func__ << " waiting for pgs to catch up (need " << need
 	       << " max_lag " << max_lag << ")" << dendl;