Commented by: Tao Lin (tao)

After I changed my connectionString's packet size to 8192, it speed up a lot! Now it took about 7 seconds to load 1066 records from database. But compare with my Delphi test project, it's still quite slow. My Delphi test application only take 2 seconds to load 1066 records.

Commented by: Nicolas (nycolas)

These days at work, we're choosing our database for our future project (in C#⁠} : Firebird or PostgreSQL.

My preference goes to Firebird but... the performance is dramatic with blobs and with the .NET Provider. With PostGreSQL and NPGSQL driver for .Net, it takes only 4-5 seconds to read 140 000 records with 5 fields and one blob per record. With Firebird and http://ADO.Net DataProvider 2.5.2, it takes about 80 seconds to do the same job...

First, I was thinking it was Firebird fault... but I tried the same query in IBExpert, and it takes only a few seconds to read 140 000 records... so I think it's a http://Firebird.net provider performance issue...

Commented by: Peter Motycak (motycak)

Hi, I'm sending a simulation process

Here is the database and an example project:
(ReadingSlowBlobs.zip): https://groups.google.com/d/msg/firebird_cz/YOjNCQaw_J4/7_9dXdruAgAJ

1. Copy the database (from the Database folder) to the server that is located in LAN network.
2. Open the project, in file named "program.cs" and then set the correct constants (path to server, port ...)
3. Run the program.
4. Loading 3000 entries through LAN takes about 27 seconds.
    Loading 3000 records locally takes about 2 seconds.
5. It should be faster.

Thank you very much for your help.

Commented by: @cincuranet

@peter Motycak: The loopback is surely faster, because the packet never hits the real network and it's just handled in the OS.

But I also compared pure `isql` with the application. I'm using `set blob all` to fetch the blob content and not only the blob id (which is what IBExpert probably did for you @nicolas, depending on settings). And both applications perform same way. The .NET did it in 14,75s and `isql` in 14,87s, which is virtually the same. See the attached image (http://tracker.firebirdsql.org/secure/attachment/13299/img.png).