The default configuration of httpclient will result in the CPoolEntry of the connection pool not being released, if the response code is not 200, 204, 400

[aiwoziyue]

<dependency>
    <groupId>org.kairosdb</groupId>
    <artifactId>client</artifactId>
    <version>3.0.0</version>
</dependency>

com.proofpoint.http.client.UnexpectedResponseException: Expected response code to be [200, 204], but was 500: Internal Server Error
	at org.kairosdb.client.response.DefaultJsonResponseHandler.handle(DefaultJsonResponseHandler.java:70) ~[client-3.0.0.jar:na]
	at org.kairosdb.client.HttpClient.execute(HttpClient.java:331) ~[client-3.0.0.jar:na]
	at org.kairosdb.client.HttpClient.postData(HttpClient.java:291) ~[client-3.0.0.jar:na]
	at org.kairosdb.client.HttpClient.postData(HttpClient.java:273) ~[client-3.0.0.jar:na]
	at org.kairosdb.client.HttpClient.query(HttpClient.java:232) ~[client-3.0.0.jar:na]
...

By default, each route has a maximum of two connections, and all others will be blocked

please help me