CODEWITHSUNDEEP
wso2wso2-business-processwso2-enterprise-integratorwso2-esb
curledUpSheep
curledUpSheep

Reputation: 413

Why does my WSO2 EI (ESB) proxy service hang for 3 minutes?

I have a BPS process that rapidly performs a lot of calls to an ESB proxy. The ESB proxy calls an ESB API, which calls the API of our own product.

Often, the BPS process pauses for exactly 3 minutes while waiting for a response from the ESB. After the 3 minutes, everything continues as if nothing happened. Using Wireshark and some additional Log mediators, I have discovered the following:

The fact that this hanging takes exactly 3 minutes should be a hint. I searched the config files for anything specifying 180 seconds, but the only ones are the http socket timeouts and the http transportReceiver's threadKeepAliveTime. If I reduce those, the BPS throws a p2p communication error instead of continuing. To me, this indicates that something somewhere in the background is still causing a 3 minute delay for some calls.

By the way, the hanging does not occur for some specific calls only. I have been testing several times, performing the exact same calls each time, and I cannot predict which call will hang or even if any call will hang at all.

Upvotes: 0

Views: 893

Answers (4)

Emmerson
Emmerson

Reputation: 71

If you enable the wire log in WSO2 you will realize NGIX is using HTTP 1.0 client in the request.

In order to fix that change your NGINX mapping to use "proxy_http_version 1.1;" and the problem will be sorted.

Cheers.

Upvotes: 1

curledUpSheep
curledUpSheep

Reputation: 413

I ended up getting WSO2 support involved in this. Apparently, I was hitting some very rare edge case which was very hard for the WSO2 engineers to reproduce.

In the end, the fix turned out to be adding the following property just before the send mediator in the proxy service:

<property name="NO_KEEPALIVE" value="true" scope="axis2"/>

Upvotes: 0

thanuja
thanuja

Reputation: 556

I had the same experience sometimes ago when I tried to call PUT or POST methods without a request body. But, by default, WSO2 ESB expects a message body to send the request to backend server when the http method is POST or PUT.

I had to either send the request with a request body (at least an empty JSON: {}) or use the property FORCE_POST_PUT_NOBODY in your APIs.

Read this post for more details on how to use FORCE_POST_PUT_NOBODY property.

Upvotes: 1

Jang-Vijay Singh
Jang-Vijay Singh

Reputation: 732

I would suggest you add at least a <send /> mediator in your faultSequence. Perhaps also add a simple makefault mediator (don't make it too complex just yet - just a static error response will do - at this stage you don't want faults originating within the faultSequence)

I suspect some error from the backend service or in the out sequence or maybe even faultSequence is not being handled - which means instead of sending a response back to your caller, the proxy hangs until time out instead

PS: It really helps if you post the source code of your proxy too

Upvotes: 1

Related Questions