---
title: Tuning the acceptor queue size
description: For optimal performance, particularly in larger deployments, PingFederate uses a non-blocking I/O model to process requests. You can tune the acceptor queue size parameters for your environment.
component: pingfederate
version: 13.1
page_id: pingfederate:performance_tuning_guide:pf_tuning_acceptor_queue_size
canonical_url: https://docs.pingidentity.com/pingfederate/13.1/performance_tuning_guide/pf_tuning_acceptor_queue_size.html
llms_txt: https://docs.pingidentity.com/pingfederate/llms.txt
docs_for_agents: https://developer.pingidentity.com/build-with-ai/docs-for-agents.md
revdate: July 5, 2022
section_ids:
  about-this-task: About this task
  steps: Steps
---

# Tuning the acceptor queue size

For optimal performance, particularly in larger deployments, PingFederate uses a non-blocking I/O model to process requests. You can tune the acceptor queue size parameters for your environment.

## About this task

If the request queue reaches its maximum size, additional requests will receive a connection refused error. If this occurs in your environment, you can increase the values of the acceptor queue size parameters `pf.admin.acceptQueueSize` and `pf.runtime.acceptQueueSize`. The `pf.admin.acceptQueueSize` parameter applies to the administrative console and the `pf.runtime.acceptQueueSize` parameter applies to the engine nodes.

## Steps

1. Stop PingFederate.

2. Open the `<pf_install>/pingfederate/bin/run.properties` file in an editor.

   |   |                                             |
   | - | ------------------------------------------- |
   |   | Consider making a backup copy of this file. |

3. Go to the following section and change the values of the `pf.admin.acceptQueueSize` and `pf.runtime.acceptQueueSize` parameters.

   ```
   # HTTP Connector Queue Size Settings
   # ----------------------------------
   # The following properties control the queue size of the HTTP connector.
   #
   # Please refer to the performance tuning guide for further tuning guidance.
   pf.admin.acceptQueueSize=512
   pf.runtime.acceptQueueSize=512
   ```

4. Save your changes and restart PingFederate.

5. For a clustered PingFederate environment, repeat the previous steps on each engine node.