Re: [ns] bug in webtraf.cc

[Haobo Yu <haoboy@isi.edu>]

I've incorporated Felix's patch into the webtraf patch for ns-2.1b6 
online. This'll also appear in tomorrow's snapshot. 

Thanks a lot.

- Haobo

On Tue, 11 Apr 2000, Felix Hernandez Campos wrote:

> Hi,
> 
> I found a bug in webtraf.cc. The code in the current snapshot only uses one
> object per page. The problem is that WebPage instances do not reschedule more
> object requests after the first one is completed. It looks like something got
> broken by the last patch.
> 
> I have fixed it by modifying WebPage::start() and WebPage::handle() in the
> following way:
> 
> inline void start() {
>   expire();
>   sched(sess_->interObj()->value());   // <---- NEW
>   curObj_++;   // <---- NEW
> }
> 
> virtual void handle(Event *e) {
>   // XXX Note when curObj_ == nObj_, we still schedule the timer
>   // once, but we do not actually send out requests. This extra
>   // schedule is only meant to be a hint to wait for the last
>   // request to finish, then we will ask our parent to delete
>   // this page.
> 
>   if (curObj_ < nObj_)
>     TimerHandler::handle(e);
> 
>   // If this is not the last object, schedule the next one.
>   // Otherwise stop and tell session to delete me.
> 
>   if (curObj_ >= nObj_) {   // <---- MODIFIED
>     sess_->donePage((void*)this);
>   } else {
>     curObj_++;
>     sched(sess_->interObj()->value());
>   }
> }
> 
> I also modified donePage() and expire() in WebTrafSession, adding an extra
> schedule to get rid of deletion problems:
> 
> void WebTrafSession::donePage(void* ClntData)
> {
>   delete (WebPage*)ClntData;
>   // If all pages are done, tell my parent to delete myself
> 
>   // extra schedule
>   if (++donePage_ > nPage_)    // <--- MODIFIED
>     mgr_->doneSession(id_);
> }
> 
> // Launch the current page
> void WebTrafSession::expire(Event *)
> {
> 
>   if (donePage_ < nPage_) {   // <---- NEW
> 
>     // Pick destination for this page
>     Node* dst = mgr_->pickdst();
>     // Make sure page size is not 0!
>     WebPage* pg = new WebPage(LASTPAGE_++, this,
>            (int)ceil(rvPageSize_->value()), dst);
> #if 0
>     printf("Session %d starting page %d, curpage %d \n",
>            id_, LASTPAGE_-1, curPage_);
> #endif
>     pg->start();
>   } else {  // <---- NEW
>     donePage((void*)this);  // <---- NEW
>   }  // <---- NEW
> 
> }
> 
> The generated traffic looks correct.
> 
> -- Felix Hernandez
> 
>