diff --git a/src/config.c b/src/config.c
index 768db1e9ab9229d8567b52b42d5ee3a3a2651c95..a36eb9a392b0ffcbd1cdfac502409d9e7e024e4f 100644
--- a/src/config.c
+++ b/src/config.c
@@ -438,7 +438,12 @@ void configSetCommand(redisClient *c) {
         if (getLongLongFromObject(o,&ll) == REDIS_ERR ||
             ll < 0) goto badfmt;
         server.maxmemory = ll;
-        if (server.maxmemory) freeMemoryIfNeeded();
+        if (server.maxmemory) {
+            if (server.maxmemory < zmalloc_used_memory()) {
+                redisLog(REDIS_WARNING,"WARNING: the new maxmemory value set via CONFIG SET is smaller than the current memory usage. This will result in keys eviction and/or inability to accept new write commands depending on the maxmemory-policy.");
+            }
+            freeMemoryIfNeeded();
+        }
     } else if (!strcasecmp(c->argv[2]->ptr,"maxmemory-policy")) {
         if (!strcasecmp(o->ptr,"volatile-lru")) {
             server.maxmemory_policy = REDIS_MAXMEMORY_VOLATILE_LRU;
diff --git a/src/redis.c b/src/redis.c
index 0656d7c294bfaace069c7f8947f40ecad30491dd..aa5a73f2abae195632463461416acf60c5c3f887 100644
--- a/src/redis.c
+++ b/src/redis.c
@@ -2578,6 +2578,11 @@ int main(int argc, char **argv) {
             redisLog(REDIS_NOTICE,"The server is now ready to accept connections at %s", server.unixsocket);
     }
 
+    /* Warning the user about suspicious maxmemory setting. */
+    if (server.maxmemory > 0 && server.maxmemory < 1024*1024) {
+        redisLog(REDIS_WARNING,"WARNING: You specified a maxmemory value that is less than 1MB (current value is %llu bytes). Are you sure this is what you really want?", server.maxmemory);
+    }
+
     aeSetBeforeSleepProc(server.el,beforeSleep);
     aeMain(server.el);
     aeDeleteEventLoop(server.el);