http2: set nghttp2_option_set_no_closed_streams

PR-URL: #23134Fixes: #23116 Reviewed-By: Matteo Collina <[email protected]> Reviewed-By: Luigi Pinca <[email protected]> Reviewed-By: James M Snell <[email protected]>

Author: davedoesdev

src/node_http2.cc

@@ -98,6 +98,10 @@ Http2Scope::~Http2Scope(){
 Http2Options::Http2Options(Environment* env, nghttp2_session_type type){
 nghttp2_option_new(&options_);
 
+// Make sure closed connections aren't kept around, taking up memory.
+// Note that this breaks the priority tree, which we don't use.
+nghttp2_option_set_no_closed_streams(options_, 1);
+
 // We manually handle flow control within a session in order to
 // implement backpressure -- that is, we only send WINDOW_UPDATE
 // frames to the remote peer as data is actually consumed by user

test/parallel/test-http2-forget-closed-streams.js

@@ -0,0 +1,53 @@
+'use strict';
+constcommon=require('../common');
+if(!common.hasCrypto){
+common.skip('missing crypto');
+}
+
+// Issue #23116
+// nghttp2 keeps closed stream structures around in memory (couple of hundred
+// bytes each) until a session is closed. It does this to maintain the priority
+// tree. However, it limits the number of requests that can be made in a
+// session before our memory tracking (correctly) kicks in.
+// The fix is to tell nghttp2 to forget about closed streams. We don't make use
+// of priority anyway.
+// Without the fix, this test fails at ~40k requests with an exception:
+// Error [ERR_HTTP2_STREAM_ERROR]: Stream closed with error code
+// NGHTTP2_ENHANCE_YOUR_CALM
+
+consthttp2=require('http2');
+constassert=require('assert');
+
+constserver=http2.createServer({maxSessionMemory: 1});
+
+server.on('session',function(session){
+session.on('stream',function(stream){
+stream.on('end',common.mustCall(function(){
+this.respond({
+':status': 200
+},{
+endStream: true
+});
+}));
+stream.resume();
+});
+});
+
+server.listen(0,function(){
+constclient=http2.connect(`http://localhost:${server.address().port}`);
+
+functionnext(i){
+if(i===10000){
+client.close();
+returnserver.close();
+}
+conststream=client.request({':method': 'POST'});
+stream.on('response',common.mustCall(function(headers){
+assert.strictEqual(headers[':status'],200);
+this.on('close',common.mustCall(()=>next(i+1)));
+}));
+stream.end();
+}
+
+next(0);
+});