add separate limits for connection buffers

allows specifying a megabyte limit for either response objects or read
buffers. this is split among all of the worker threads.

useful if connection limit is extremely high and you want to
aggressively close connections if something
happens and all connections become active at the same time.

missing runtime tuning.

1 files changed, 20 insertions, 0 deletions

diff --git a/thread.c b/thread.c
index 2b91f3e..ebb0379 100644
--- a/thread.c
+++ b/thread.c
@@ -411,12 +411,32 @@ static void setup_thread(LIBEVENT_THREAD *me) {
         fprintf(stderr, "Failed to create response cache\n");
         exit(EXIT_FAILURE);
     }
+    // Note: we were cleanly passing in num_threads before, but this now
+    // relies on settings globals too much.
+    if (settings.resp_obj_mem_limit) {
+        int limit = settings.resp_obj_mem_limit / settings.num_threads;
+        if (limit < sizeof(mc_resp)) {
+            limit = 1;
+        } else {
+            limit = limit / sizeof(mc_resp);
+        }
+        cache_set_limit(me->resp_cache, limit);
+    }
 
     me->rbuf_cache = cache_create("rbuf", READ_BUFFER_SIZE, sizeof(char *), NULL, NULL);
     if (me->rbuf_cache == NULL) {
         fprintf(stderr, "Failed to create read buffer cache\n");
         exit(EXIT_FAILURE);
     }
+    if (settings.read_buf_mem_limit) {
+        int limit = settings.read_buf_mem_limit / settings.num_threads;
+        if (limit < READ_BUFFER_SIZE) {
+            limit = 1;
+        } else {
+            limit = limit / READ_BUFFER_SIZE;
+        }
+        cache_set_limit(me->rbuf_cache, limit);
+    }
 
 #ifdef EXTSTORE
     me->io_cache = cache_create("io", sizeof(io_wrap), sizeof(char*), NULL, NULL);