What's the data size limitation for EWS server accepts data exchange request from client

[sesa197614_brid]

Laterly, I am testing the performance to one of my custom EWS server in SmartConnector, in my usage, ES will be as EWS client to consume data from server. And I found some bottleneck, please help analysis the root cause:

1. when ES poll value for 1300 points at one time, by Wireshark, I found it will take around 4 seconds to get the response from EWS server, and in my ES, I will get all updated value around 6 seconds, not too bad.

• Request:

• Response:

2. The way I use to poll data is using listview to refresh value to a folder which including 1300 points.

3. However, when I try 1700 points in ES at one time, SmartConnector will response with error message "Request Entity too large". ,the request file data is 82206 bytes already.

4. I found the ES as Ews client to poll value from EWS server, it can't send request command by pages but only in one command, which cause the request data to be too large.

My question:

• 1. Is the the limitation of request data from EWS protocol itself or from SmartConnector? or some other reason?
• If it is really limitation, what's the actual limitation data?
• Can't EWS client in ES polling value by pages? any setting for this?

Without clear the above bottleneck, I can only say my server support 1300-1500 points max only(considering worst case of usage).

BR

-Austen Yin

[JeffBowman]

HI Austen,

We are looking into the max SmartConnector 'Serve' request size.

In the mean time, can you send us the save packet capture (.pcap file) and not just the screenshot? It will make it easier for us to understand exactly what is going on.

Regards,

-Jeff

[sesa197614_brid]

Hi Jeff:

Please find the attached file for your reference, I carry out two requests: one with 1300 points as acceptable data size request, and the other one with 1700 points as too large data size request.

BR

Austen

[sesa197614_brid]

Hi:

@Jeffrey Bowman, @Mark Stemmler

Any updated of it?

Cheers

Austen

[sesa180908_brid]

Austen,

Sorry for the late response.  We are still investigating and will update when we have more information. 

[sesa180908_brid · Accepted solution]

Austen,

We completed our investigation today and identified the issue.  While most of SmartConnector leverages OWin (which has it's own built in request limits), the EWS Serve capabilities are a little different.  For that, normal WCF binding settings are mostly hard coded because we do a "code based" (as opposed to a configuration file based) setup of the ServiceHost's Binding instance. 

Unfortunately, that too had a relatively small maximum message size.  While we intend to make this configurable in the future, we are going to issue a patch to 2.2 which will extend this limit from the current size of 65536 bytes to 4M.  This should address the short term issue.

We hope to get this patch out in the next day or so. 

Thanks for your patience on this issue.