Initial threadpool implementation for MariaDB 5.5

1 files changed, 47 insertions, 0 deletions

diff --git a/sql/threadpool.h b/sql/threadpool.h
new file mode 100644
index 00000000000..0694981d76f
--- /dev/null
+++ b/sql/threadpool.h
@@ -0,0 +1,47 @@
+
+/* Threadpool parameters */
+#ifdef _WIN32
+extern uint threadpool_min_threads;  /* Minimum threads in pool */
+#else
+extern uint threadpool_idle_timeout; /* Shutdown idle worker threads  after this timeout */
+extern uint threadpool_size; /* Number of parallel executing threads */
+extern uint threadpool_stall_limit;  /* time interval in 10 ms units for stall checks*/
+#endif
+extern uint threadpool_max_threads;  /* Maximum threads in pool */
+
+/*
+  Threadpool statistics
+*/
+struct TP_STATISTICS
+{
+  /* Current number of worker thread. */
+  volatile int num_worker_threads;
+  /* Current number of idle threads. */
+  volatile int num_waiting_threads;
+  /* Number of login requests are queued but not yet processed. */
+  volatile int pending_login_requests;
+  /* Number of threads that are starting. */
+  volatile int pending_thread_starts;
+  /* Number of threads that are being shut down */
+  volatile int pending_thread_shutdowns;
+  /* Time (in milliseconds) since pool is blocked (num_waiting_threads is 0) */
+  ulonglong pool_block_duration;
+  /* Maximum duration of the pending login, im milliseconds. */
+  ulonglong pending_login_duration; 
+  /* Time since last thread was created */
+  ulonglong time_since_last_thread_creation;
+  /* Number of requests processed since pool monitor run last time. */
+  volatile int requests_dequeued;
+  volatile int requests_completed;
+};
+
+extern TP_STATISTICS tp_stats;
+
+
+/* Functions to set threadpool parameters */
+extern void tp_set_min_threads(uint val);
+extern void tp_set_max_threads(uint val);
+
+/* Activate threadpool scheduler */
+extern void tp_scheduler(void);
+