DataContext.Submit使用奇怪的堆栈跟踪更改超时

我为期两年的大项目两周前刚刚上线。虽然我们遇到了正常的发射问题，但它非常成功，只是出现了一个奇怪的错误。

这个故事已经改变了；实际项目与电影票无关。

我们的网站允许电影院的员工打印电影票。一旦他们决定了要打印的内容，他们就会转到打印票证网页并单击"打印"。这会将一批数据发送到电影票打印机，几秒钟后，用户的票打印机开始打印电影票。

我们给票编号，并希望确保没有使用重复的号码。代码看起来是这样的：

using (TicketContext context = new TicketContext(ConnectionString)) {
    // call a stored proc that allocates a group of tickets with fancy transaction stuff
    var result = context.GetNextTicketGroup(tickets.Count).FirstOrDefault();
    if (result == null || !result.Column1.HasValue || result.Column1.Value == -1)
        return "There was an error allocating ticket numbers";
    int ticketNumber = result.Column1.Value;
    // Put the ticket numbers in the ticket objects
    int i;
    for (i = 0; i < ticketCount; i++) {
        tickets[i].TicketNumber = ticketNumber + i;
    }
    for (i = 0; i < ticketCount; i++) {
        // Convert the ticket object that we've been working with into 
        // a record that is the kind we have in the database and 
        // put that into the database.  CreateTicket() doesn't do any 
        // database stuff directly.
        DBTicket newticket = CreateTicket(ticket[i]); 
        context.Tickets.InsertOnSubmit(newticket);
    }
    // Each ticket is tied to an Issuance ID - Get a list of IssuanceIDs from the
    // list of tickets and mark them as printed
    var IDs = items.Select(id => id.IssuanceID).Distinct();
    foreach (Guid g in IDs) {
        var Issuance = context.TicketIssuances.Where(ti => ti.ID == g).FirstOrDefault();
        if(Issuance != null) {
            Issuance.Printed = true;
        }
    }
    // Submit the changes to the database
    context.SubmitChanges();
    // Send the printers to the ticket printer via a web service
    using (TicketService.TicketSoapClient ssc = new TicketService.TicketSoapClient()) {
        var a = tickets.ToArray();
        if (ssc.PrintTickets(a) == false)
            return "Error printing.";
    }
}   // LINE 392

现在，不寻常的部分是context.SubmitChanges()超时，但堆栈跟踪看起来是这样的：

 [...]  
 at System.Data.Linq.ChangeDirector.StandardChangeDirector.Insert(TrackedObject item)
 at System.Data.Linq.ChangeProcessor.SubmitChanges(ConflictMode failureMode)
 at System.Data.Linq.DataContext.SubmitChanges(ConflictMode failureMode)
 at Portal.Tickets.PrintTickets.PrintTicketList(List`1 items) in d:'Source'PrintTickets.aspx.cs:line 392
 at Portal.Tickets.PrintTickets.btnPrintTickets_Click(Object sender, EventArgs e) in d:'Source'PrintTickets.aspx.cs:line 236
 at System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument)
 at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)

我调出了上面代码中的392行；请注意，这是在datacontext超出范围的时候，早在应该发生超时之后。

这些小工作肯定不会因为某种僵局或其他什么而超时；我们一次只将数十条记录放入数据库，并且服务器没有承受过大的负载。99%以上的工作提交都很顺利，只有一小部分出现了这个错误，但当他们出现这个错误时，其中几个人在几分钟内就出现了。我倾向于完全归咎于数据库服务器，除了奇怪的堆栈跟踪。有什么见解吗？