From 4634ac484a03f88f716429712504e7c354441c0b Mon Sep 17 00:00:00 2001
From: Tyler Neely <tylerneely@gmail.com>
Date: Wed, 12 Oct 2022 18:19:06 +0200
Subject: [PATCH 1/2] Optimize simulator RNG usage (#590)

This causes instructions for `basic_request.cpp` to drop from 281 million to 28 million
---
 src/io/simulator/simulator_handle.cpp | 6 ++----
 src/io/simulator/simulator_handle.hpp | 2 ++
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/io/simulator/simulator_handle.cpp b/src/io/simulator/simulator_handle.cpp
index fe4bc8c1f..9fa16fae3 100644
--- a/src/io/simulator/simulator_handle.cpp
+++ b/src/io/simulator/simulator_handle.cpp
@@ -73,8 +73,7 @@ bool SimulatorHandle::MaybeTickSimulator() {
 
     // We tick the clock forward when all servers are blocked but
     // there are no in-flight messages to schedule delivery of.
-    std::poisson_distribution<> time_distrib(50);
-    Duration clock_advance = std::chrono::microseconds{time_distrib(rng_)};
+    const Duration clock_advance = std::chrono::microseconds{time_distrib_(rng_)};
     cluster_wide_time_microseconds_ += clock_advance;
 
     MG_ASSERT(cluster_wide_time_microseconds_ < config_.abort_time,
@@ -93,8 +92,7 @@ bool SimulatorHandle::MaybeTickSimulator() {
   auto [to_address, opaque_message] = std::move(in_flight_.back());
   in_flight_.pop_back();
 
-  std::uniform_int_distribution<int> drop_distrib(0, 99);
-  const int drop_threshold = drop_distrib(rng_);
+  const int drop_threshold = drop_distrib_(rng_);
   const bool should_drop = drop_threshold < config_.drop_percent;
 
   if (should_drop) {
diff --git a/src/io/simulator/simulator_handle.hpp b/src/io/simulator/simulator_handle.hpp
index 7ad1d795a..3adf2b7b0 100644
--- a/src/io/simulator/simulator_handle.hpp
+++ b/src/io/simulator/simulator_handle.hpp
@@ -51,6 +51,8 @@ class SimulatorHandle {
   std::set<Address> blocked_on_receive_;
   std::set<Address> server_addresses_;
   std::mt19937 rng_;
+  std::uniform_int_distribution<int> time_distrib_{5, 50};
+  std::uniform_int_distribution<int> drop_distrib_{0, 99};
   SimulatorConfig config_;
 
   void TimeoutPromisesPastDeadline() {

From 5347c06d7614dc13311819aa7e8e2c2c7a66a7ed Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marko=20Budiseli=C4=87?= <marko.budiselic@memgraph.com>
Date: Fri, 14 Oct 2022 11:59:50 +0200
Subject: [PATCH 2/2] Add shutdown of `LocalSystem` during the shutdown process
 (#592)

---
 src/memgraph.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/memgraph.cpp b/src/memgraph.cpp
index 023135478..7d821b3e6 100644
--- a/src/memgraph.cpp
+++ b/src/memgraph.cpp
@@ -690,7 +690,7 @@ int main(int argc, char **argv) {
   std::optional<memgraph::telemetry::Telemetry> telemetry;
 
   // Handler for regular termination signals
-  auto shutdown = [&server, &interpreter_context] {
+  auto shutdown = [&server, &interpreter_context, &ls] {
     // Server needs to be shutdown first and then the database. This prevents
     // a race condition when a transaction is accepted during server shutdown.
     server.Shutdown();
@@ -698,6 +698,7 @@ int main(int argc, char **argv) {
     // connections we tell the execution engine to stop processing all pending
     // queries.
     memgraph::query::v2::Shutdown(&interpreter_context);
+    ls.ShutDown();
   };
 
   InitSignalHandlers(shutdown);