Visual Basic Discussion Boards

Let me explain:
Suppose the scheduler runs for the first time and it picks 5 projects(5 threads). Supposing each project has 1000 contacts to whom the mail needs to be sent.
Now the scheduler is scheduled to run after every 1 min. So after 1 min the second instance of the scheduler starts and it picks 5 more projects(5 more threads). Now these new threads keep on waiting till the mails are sent to the contacts of first 5000 contacts. It is only after these mails are sent the threads in the second instance start.
Our system sends about 600 mails in a minute. Even if the mails are not sent for the previous instance the threads in the second instance should atleast start.

OK, it sounds like the mail class can only send one mail at a time ( which seems possible ). So, as I said, the question is, why does it have to run every minute ?

Christian Graus - C++ MVP

'Why don't we jump on a fad that hasn't already been widely discredited ?' - Dilbert

We need to run it quite frequently because the projects added by our clients should be serviced as soon as they are added.
Even if we increase the time of executing the scheduler it may solve the problem temporarily. But my point is why should the threads wait, I mean this should not happen (conceptually atleast!).

Sandeep_S wrote:
We need to run it quite frequently because the projects added by our clients should be serviced as soon as they are added.

If they wait more than 60 seconds, the world will end ?

Really, you should have a single queue, which gets added to, not several queues. It seems to me that the answer is almost certainly that your method of sending emails is written this way, so a single queue is formed, even if you didn't impliment your app this way.

Christian Graus - C++ MVP

'Why don't we jump on a fad that hasn't already been widely discredited ?' - Dilbert

This is the way we have implemented the app:

Dim objThreadList As ArrayList
Sub Main()
Schedule()
End Sub

Public Sub Schedule()
For Counter = 0 To dsProject.Tables(0).Rows.Count - 1 ''Loop runs for each project
CallThread(dsProject.Tables(0).Rows(Counter), Counter)
Next
End Sub

Public Sub CallThread(ByVal drProject As DataRow, ByVal counter As Integer)
objThreadList.Add(New Thread(AddressOf ThreadProcess))
drThread = drProject
objThreadList(counter).Start()
End Sub

Public Sub ThreadProcess()
Dim objClsProject As New clsProjectThread
objClsProject.ActualProcess()
End Sub

Public Sub ActualProcess()
'Code for sending mail
End Sub

I don't see how that proves anything. Like I said, it seems to me like the code for sending emails is forming a queue of mails to send. The mails from the first thread, get sent first.

Christian Graus - C++ MVP

'Why don't we jump on a fad that hasn't already been widely discredited ?' - Dilbert

Sandeep_S wrote:
the projects picked by this instance have to wait for completion of all the threads belonging to the previous instance

Why?

---
Year happy = new Year(2007);

Guffa wrote:
Why?

That's what I can't figure out.

Don't you even know why you are asking the question?

How have you come to the conclusion that the first thread has to finish before starting the next?

---
Year happy = new Year(2007);

Because I have monitored the working of the scheduler.
The thing I am unable to understand is why does it require the threads of first instance to be completed before starting the threads of the second instance (Because this is what is happening).

The threads work independently, unless you prevent them to. If the threads are waiting for each other, it has nothing to do with the threading. It's either a problem with performance as you are trying to do too much at the same time, or a limitation in some resource that the threads are using, like for instance the SMTP server.

---
Year happy = new Year(2007);

So can I safely assume that my code is fine and I have to find out the problem elsewhere may be in the server or some other resource.

Do you mean to say that the threads of the second instance are not even started? OR that the threads of the second instance are started but no mails are sent? If second case is true, then the bottleneck most probably is the SMTP server. Did you check the outbox of the SMTP server if possible?

Alternatively, you can use a timestamp to indicate which users/projects have been sent an email in the last 15 mins or so, and not re send the emails to them. This way, at least 10 instances of your application (1 per minute for 10 mins) will not attempt to send 1000s of emails. IMHO, the user will be very annoyed if he really receives a mail per minute reminding him the same thing!

Shreekar

Yes, the threads of second instance are not even started.

How are you starting the application after each minute? The problem might be there.

Shreekar

I use Windows Scheduling. ie. I have registered the application with Windows Scheduled tasks. It automatically executes after 1 minute.

OK Then you need to eliminate the reasons. Write another app that does something for more than a minute - like counting from 1 to 1000000, then enumerating files in a folder , writing to a log file etc.
Then schedule this new app similarly for each minute and study whether this displays the same behaviour, if it does, the problem is the scheduler, and I dont know what can be done about it.
If not, the problem is the mail sending code/SMTP.

Shreekar

Fine, I will figure out this. But most probably I think the problem is with the Windows Scheduler. I think we should make this a windows service instead of scheduling it at intervals. The windows service would run continously without stopping.
What do you say?

Yes, it would then run the way I was saying it should, a single queue.

Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog

But the threading will still remain, right?

Hi
Can I display the page No and page total on DataReport VB6 ,, or not
I try alot without any result ..
I need any one to help .. Rose | [Rose]

jooooo

I search and found it

in your page footer, add a label, and set the caption property to:

Page %p of %P

jooooo

Hi,
I'm using crystal report viewer for loading my Crystal Reports in form.When I'm selecting a record from a datagrid,I'll be generating the report for the particular InvoiceNo.Both the Datagrid and Crystal Report Viewer are in same form.
When I'm selecting the record,the report is generated.After that when I refresh,the datagrid is displayed.After Refres,When I select a record,the report is generated,but on click of Crystal Report Viewer,report is being generated for other InvoiceNo instead of the selected one.

Can anyone let me know the cause for this and How could we resolve this?

Thank you,

Regards,
Deepa!

You need to show some code related to selection of InvoiceNo in grid so that we can help.

Shreekar

Hi,

For Datagrid Display!
private void ugdDeliveryOrderListLoad(string vCustNo)
{
StringBuilder stbSQLStatement1 = new StringBuilder();
stbSQLStatement1.Append(" select dbo.MARTblInvoice.[InvoiceNo] As [Delivery Note No] ");
stbSQLStatement1.Append(", dbo.MARTblInvoice.CustNo ");
stbSQLStatement1.Append(", dbo.MARTblInvoice.SoldToCustName ");
stbSQLStatement1.Append(", dbo.MARTblInvoice.DeliverToCustName ");
stbSQLStatement1.Append(", dbo.MARTblInvoice.IssuedDate ");
stbSQLStatement1.Append(" from dbo.MARTblInvoice left outer join dbo.MARTblCustomer ");
stbSQLStatement1.Append(" on dbo.MARTblInvoice.CustNo = dbo.MARTblCustomer.CustNo ");
//stbSQLStatement1.Append(" where dbo.MARTblInvoice.[InvoiceNo] = "+ ugDeliveryOrderLlist.ActiveRow["Delivery Note No"] + " ");
stbSQLStatement1.Append(" Where dbo.MARTblInvoice.IsCreateDeliveryOrder = 1 ");
stbSQLStatement1.Append(" and dbo.MARTblInvoice.InvoiceNo not like 'D%' ");
stbSQLStatement1.Append(" and dbo.MARTblInvoice.CustNo like '"+vCustNo+ "%' ");
stbSQLStatement1.Append(" and dbo.MARTblInvoice.DOPrintCounter <= 2 ");
stbSQLStatement1.Append(" and dbo.MARTblInvoice.InvoiceNo in ");
stbSQLStatement1.Append(" ((Select InvoiceNo From MARTblInvoiceDetailProduct) ");
stbSQLStatement1.Append(" UNION ALL ");
stbSQLStatement1.Append(" (Select InvoiceNo From MARTblInvoiceDetailNonProduct)) ");
stbSQLStatement1.Append(" and dbo.MARTblCustomer.GroupKeyID like '"+ GroupKeyID +"%' ");
stbSQLStatement1.Append(" order by [Delivery Note No] Desc ");

DataSet dtsResult1 = new DataSet();
dtsResult1 = QueryData(stbSQLStatement1.ToString());

ugDeliveryOrderLlist.DataSource = dtsResult1;

if(dtsResult1.Tables[0].Rows.Count == 0)
{
MessageBox.Show("No Results Found. ","DuPont MARS",MessageBoxButtons.OK,MessageBoxIcon.Exclamation);
}
ugDeliveryOrderLlist.DataBind();
}

On selecting the record,

Grid_AfterSelectChange event
pnlReport.Visible = true;
DisplayReport();
utmDataMaintenance.Tools["Print"].SharedProps.Enabled = true;

I'm using crv(Crystal Report Viewer)Is that the reason,Everytime when I scroll on the generated report,report is being generated again for other invoice no.

What might be the workaround for this?

Thank you,

Regards,

Deepa.