From 121e3c7b8f9ab8ac41eb7ee82b96b04f88d6a7ae Mon Sep 17 00:00:00 2001
From: Vlad Zolotarov <vladz@scylladb.com>
Date: Wed, 12 Jul 2017 18:16:02 -0400
Subject: [PATCH 1/2] utils::loading_cache: make a timer use a
 loading_cache_clock_type clock as a source

Signed-off-by: Vlad Zolotarov <vladz@scylladb.com>
---
 utils/loading_cache.hh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/utils/loading_cache.hh b/utils/loading_cache.hh
index ddf78436df..61d929d9d1 100644
--- a/utils/loading_cache.hh
+++ b/utils/loading_cache.hh
@@ -378,7 +378,7 @@ private:
     std::chrono::milliseconds _refresh;
     logging::logger& _logger;
     std::function<future<Tp>(const Key&)> _load;
-    timer<lowres_clock> _timer;
+    timer<loading_cache_clock_type> _timer;
 };
 
 }

From 76ea74f3fd259c63b0bc8ddacbac5ba52dd0c941 Mon Sep 17 00:00:00 2001
From: Vlad Zolotarov <vladz@scylladb.com>
Date: Wed, 12 Jul 2017 18:21:02 -0400
Subject: [PATCH 2/2] utils::loading_cache: arm the timer with a period equal
 to min(_expire, _update)

Arm the timer with a period that is not greater than either the permissions_validity_in_ms
or the permissions_update_interval_in_ms in order to ensure that we are not stuck with
the values older than permissions_validity_in_ms.

Fixes #2590

Signed-off-by: Vlad Zolotarov <vladz@scylladb.com>
---
 utils/loading_cache.hh | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/utils/loading_cache.hh b/utils/loading_cache.hh
index 61d929d9d1..a5bf727b81 100644
--- a/utils/loading_cache.hh
+++ b/utils/loading_cache.hh
@@ -182,8 +182,9 @@ public:
             throw exceptions::configuration_exception("loading_cache: caching is enabled but refresh period and/or max_size are zero");
         }
 
+        _timer_period = std::min(_expiry, _refresh);
         _timer.set_callback([this] { on_timer(); });
-        _timer.arm(_refresh);
+        _timer.arm(_timer_period);
     }
 
     ~loading_cache() {
@@ -364,7 +365,7 @@ private:
             return now();
         }).finally([this, timer_start_tp] {
             _logger.trace("on_timer(): rearming");
-            _timer.arm(timer_start_tp + _refresh);
+            _timer.arm(timer_start_tp + _timer_period);
         });
     }
 
@@ -376,6 +377,7 @@ private:
     size_t _max_size;
     std::chrono::milliseconds _expiry;
     std::chrono::milliseconds _refresh;
+    loading_cache_clock_type::duration _timer_period;
     logging::logger& _logger;
     std::function<future<Tp>(const Key&)> _load;
     timer<loading_cache_clock_type> _timer;