Slow response time via VPN

Discussion of open issues, suggestions and bugs regarding UniDAC (Universal Data Access Components) for Delphi, C++Builder, Lazarus (and FPC)
Post Reply
CristianP
Posts: 79
Joined: Fri 07 Dec 2012 07:44
Location: Timișoara, Romania

Slow response time via VPN

Post by CristianP » Wed 20 May 2020 15:23

Hello,

Delphi 10.3.3, UniDAC 8.1.2

One of our customers do use a VPN connection on port 3600 (not standard port) to connect to a MySQL server.
The issue is that some very light queries that returns only a row (no blobs) needs 5 seconds.
Using HeidiSQL with libmysql.dll trough same VPN is fast (milliseconds).
Without VPN (in local network) is also fast. VPN is used to connect from outside.
Using libmysql.dll is now deprecated and I don't know what to do.
I will try probably to see if I can see something with Wireshark.

What do you recommend?

CristianP
Posts: 79
Joined: Fri 07 Dec 2012 07:44
Location: Timișoara, Romania

Re: Slow response time via VPN

Post by CristianP » Thu 21 May 2020 14:30

It was an TUniQuery with UniDirectional = True.
Why only on VPN it was so slow I can't understand.
5 sec. vs. 80 msec. (in internet).
In some cases it was only a table with a few rows and query returned one row with a short string. On VPN with UniDirectional=True it was very slow.
I don't have more time now to investigate.

ViktorV
Devart Team
Posts: 3168
Joined: Wed 30 Jul 2014 07:16

Re: Slow response time via VPN

Post by ViktorV » Thu 21 May 2020 15:00

Unfortunately, we haven't been able to reproduce the issue.
Please create an example demonstrating the incorrect behavior and send it to us, along with test credentials for logging in to your server via VPN, through the contact form (https://devart.com/company/contactform.html). We'll try to investigate the issue to come up with a solution.

Post Reply