diff --git a/src/shrpx_io_control.cc b/src/shrpx_io_control.cc
index 38d75753..f43a2576 100644
--- a/src/shrpx_io_control.cc
+++ b/src/shrpx_io_control.cc
@@ -37,8 +37,6 @@ IOControl::IOControl(RateLimit *lim) : lim_(lim), rdbits_(0) {}
 
 IOControl::~IOControl() {}
 
-void IOControl::set_lim(RateLimit *lim) { lim_ = lim; }
-
 void IOControl::pause_read(IOCtrlReason reason) {
   rdbits_ |= reason;
   if (lim_) {
diff --git a/src/shrpx_io_control.h b/src/shrpx_io_control.h
index f3dd24f5..9baf95aa 100644
--- a/src/shrpx_io_control.h
+++ b/src/shrpx_io_control.h
@@ -41,7 +41,6 @@ class IOControl {
 public:
   IOControl(RateLimit *lim);
   ~IOControl();
-  void set_lim(RateLimit *lim);
   void pause_read(IOCtrlReason reason);
   // Returns true if read operation is enabled after this call
   bool resume_read(IOCtrlReason reason);