From 3c6a6c46d5808d6c42ed4dcfb441bad64366686b Mon Sep 17 00:00:00 2001
From: Sage Weil <sage@redhat.com>
Date: Thu, 3 Aug 2017 16:37:36 -0400
Subject: [PATCH] os/bluestore: set deferred_aggressive if initial throttle get
 fails

This ensures that in-progress transactions with deferred writes queue their
IO immediately.  Otherwise, we may end up waiting indefinitely.

This is a biggish hammer.

Signed-off-by: Sage Weil <sage@redhat.com>
---
 src/os/bluestore/BlueStore.cc | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/os/bluestore/BlueStore.cc b/src/os/bluestore/BlueStore.cc
index 7276b60fa40..baf4eff96b3 100644
--- a/src/os/bluestore/BlueStore.cc
+++ b/src/os/bluestore/BlueStore.cc
@@ -8808,9 +8808,13 @@ int BlueStore::queue_transactions(
   if (txc->deferred_txn) {
     // ensure we do not block here because of deferred writes
     if (!throttle_deferred_bytes.get_or_fail(txc->cost)) {
+      dout(10) << __func__ << " failed get throttle_deferred_bytes, aggressive"
+	       << dendl;
+      ++deferred_aggressive;
       deferred_submit_all();
       throttle_deferred_bytes.get(txc->cost);
-    }
+      --deferred_aggressive;
+   }
   }
   utime_t tend = ceph_clock_now();