salesforce : C# Api compare to ApexDataloader - salesforce

Question

I have performance issue on salesforce
I am trying to load table from salesforce into excel cvs, for that used, I tested the ApexDataLoader and found out that to load whole lead table for my organization take around 4~5 min, and have around 60,000 records.
Now I want to do the same with a C# code, for that I write this code:
var user = "xxx";
var password = "xxx";
var token = "xxx";
var sforceService = new SforceService();
var login = sforceService.login(user, String.Concat(password, token));
sforceService.Url = login.serverUrl;
sforceService.SessionHeaderValue = new SessionHeader { sessionId = login.sessionId };
var query = "The full query that I took from ApexDataLoder";
var startTime = DateTime.Now.TimeOfDay;
var firstTime = DateTime.Now.TimeOfDay;
var result = sforceService.query(query);
int i = 0;
while (!result.done)
{
var endTime = DateTime.Now.TimeOfDay;
Debug.Print(endTime.Subtract(startTime) + " " + i * result.records.Count() + " - " + (i + 1) * result.records.Count() +
" Time from start: " + endTime.Subtract(firstTime));
startTime = DateTime.Now.TimeOfDay;
result = sforceService.queryMore(result.queryLocator);
i++;
}
After few lines I saw that I read only 2000 lines in total (out of 60,000) in 2 miniuts.
That's mean that to get the whole table I will need 60 min.
Why there is so big difference between that ApexDataLoader (5 min) to my code? what I am doing wrong?
Thanks for the help!

Answer 1

I found 2 things that really improve performance,
one, set up the EnableDecompression to true
sforceService.EnableDecompression = true;
And the second is based on this thread, it is better to do a query "select Id from Lead" and collect all the id's and then do a multi thread processing to get the data with the retrieve function.
Hope that will help people and if someone have any other improvement tricks, please let me know