test/perf: Add chunked_fifo forward scanning test

Here the fifo stores pointers to elements, to behave like array of
pointers does, yet avoiding large (re)allocations on append.

Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>

Author: xemul

tests/perf/container_perf.cc

@@ -27,6 +27,7 @@
 #include <seastar/core/chunked_fifo.hh>
 #include <seastar/core/circular_buffer.hh>
 #include <seastar/util/split-list.hh>
+#include <seastar/core/chunked_fifo.hh>
 #include <seastar/testing/random.hh>
 
 using trivial_elem = int;
@@ -262,6 +263,8 @@ class sum_perf {
     using split_list = seastar::internal::split_list<element, 16, &element::sl_next>;
     split_list _split_list_16;
 
+    seastar::chunked_fifo<element*, 128> _chunked_fifo;
+
 public:
     void init_once(unsigned nr) {
         if (_elements.size() != 0) {
@@ -286,11 +289,13 @@ class sum_perf {
 
         // Finally -- populate collections
         _array_of_pointers.reserve(nr);
+        _chunked_fifo.reserve(nr);
         for (unsigned i = 0; i < nr; i++) {
             element* e = &_elements[idx[i]];
             _array_of_pointers.push_back(e);
             _singly_linked_list.push_back(*e);
             _split_list_16.push_back(e);
+            _chunked_fifo.push_back(e);
         }
     }
 
@@ -332,6 +337,14 @@ class sum_perf {
         return ret;
     }
 
+    uint64_t sum_fifo() const noexcept {
+        uint64_t ret = 0;
+        for (auto i = _chunked_fifo.begin(); i != _chunked_fifo.end(); i++) {
+            ret += (*i)->value;
+        }
+        return ret;
+    }
+
     template <unsigned N, uint64_t (sum_perf::*Fn)() const noexcept>
     auto do_test() {
         init_once(N);
@@ -442,3 +455,28 @@ PERF_TEST_F(sum_perf, sum_sl16_100000) {
 PERF_TEST_F(sum_perf, sum_sl16_1000000) {
     return sum_perf::do_test<1000000, &sum_perf::sum_sl16>();
 }
+
+// Chunked fifo
+PERF_TEST_F(sum_perf, sum_fifo_10) {
+    return sum_perf::do_test<10, &sum_perf::sum_fifo>();
+}
+
+PERF_TEST_F(sum_perf, sum_fifo_100) {
+    return sum_perf::do_test<100, &sum_perf::sum_fifo>();
+}
+
+PERF_TEST_F(sum_perf, sum_fifo_1000) {
+    return sum_perf::do_test<1000, &sum_perf::sum_fifo>();
+}
+
+PERF_TEST_F(sum_perf, sum_fifo_10000) {
+    return sum_perf::do_test<10000, &sum_perf::sum_fifo>();
+}
+
+PERF_TEST_F(sum_perf, sum_fifo_100000) {
+    return sum_perf::do_test<100000, &sum_perf::sum_fifo>();
+}
+
+PERF_TEST_F(sum_perf, sum_fifo_1000000) {
+    return sum_perf::do_test<1000000, &sum_perf::sum_fifo>();
+}