diff --git a/db/commitlog/commitlog.cc b/db/commitlog/commitlog.cc
index 0a798a5de7..c5f8dae381 100644
--- a/db/commitlog/commitlog.cc
+++ b/db/commitlog/commitlog.cc
@@ -1513,28 +1513,45 @@ void db::commitlog::segment_manager::flush_segments(uint64_t size_to_remove) {
         high = replay_position(high.id + 1, 0);
     }
 
-    auto n = size_to_remove;
+    // Now get a set of used CF ids:
+    std::unordered_set<cf_id_type> ids;
 
-    if (size_to_remove != 0) {
-        for (auto& s : _segments) {
-            if (n <= s->size_on_disk()) {
-                high = replay_position(s->_desc.id, db::position_type(s->size_on_disk()));
+    uint64_t n = size_to_remove;
+    uint64_t flushing = 0;
+
+    for (auto& s : _segments) {
+        // if a segment is allocating, it should be included in flush request,
+        // because we cannot free anything there anyway. If a segment is allocating,
+        // it is the last one, so just break.
+        if (s->is_still_allocating()) {
+            break;
+        }
+
+        auto rp = replay_position(s->_desc.id, db::position_type(s->size_on_disk()));
+        if (rp <= _flush_position) {
+            // already requested.
+            continue;
+        }
+
+        auto size = s->size_on_disk();
+        auto waste = s->_waste;
+
+        flushing += size - waste;
+
+        for (auto& id : s->_cf_dirty | boost::adaptors::map_keys) {
+            ids.insert(id);
+        }
+
+        if (size_to_remove != 0) {
+            if (n <= size) {
+                high = rp;
                 break;
             }
             n -= s->size_on_disk();
         }
     }
 
-    // Now get a set of used CF ids:
-    std::unordered_set<cf_id_type> ids;
-    auto e = std::find_if(_segments.begin(), _segments.end(), std::mem_fn(&segment::is_still_allocating));
-    std::for_each(_segments.begin(), e, [&ids](sseg_ptr& s) {
-        for (auto& id : s->_cf_dirty | boost::adaptors::map_keys) {
-            ids.insert(id);
-        }
-    });
-
-    clogger.debug("Flushing ({} MB) to {}", size_to_remove/(1024*1024), high);
+    clogger.debug("Flushing ({} MB) to {}", flushing/(1024*1024), high);
 
     // For each CF id: for each callback c: call c(id, high)
     for (auto& f : callbacks) {
@@ -1546,6 +1563,8 @@ void db::commitlog::segment_manager::flush_segments(uint64_t size_to_remove) {
             }
         }
     }
+
+    _flush_position = high;
 }
 
 future<db::commitlog::segment_manager::sseg_ptr> db::commitlog::segment_manager::allocate_segment_ex(descriptor d, named_file f, open_flags flags) {