On Wed, Jul 15, 2009 at 01:55:49AM -0000, Theodore Ts'o wrote:                  
> Eric,                                                                         
>                                                                               
> The problem is that your problem may be very different from other             
> peoples' problem.   First of all, in your test, you are continually           
> dirtying the page cache with "cp /dev/zero /mnt/bigfile".    This brings      
> in filesystem effects, and VM effects, and so it's hard to tell what is       
> actually going on.                                                            
                                                                                
I was showing the results of the test that Simon propoesed a few posts          
earlier. Sorry I didn't attribute my reply properly. It was in response to      
the following:                                                           

Simon Holm Th\370gersen  wrote on 2009-06-09:                                   
> It should literally be something as simple as the following                   
> (cp bigfile /media/disk/ &) ; sleep 10 ; time echo foo > /media/disk/bar      
> If the time is really in seconds as you seem to suggest it is                 
> interesting I'd say.                                                          
                                                                                
Anyway I did also attach iostat output from during the test.                    
                                                                                                
> And certainly the test which you did "(cp /dev/zero /media/disk/bigfile       
> &); sleep 10 ; time echo foo > /media/disk/test" is not one that we can       
> replicate on Windows, so the assertion that something is wrong is also        
> not something which is immediately obvious given the very limited amount      
> of information you have given.   Maybe it's *somewhere* in this bug           
> report, bug this is why it is really not useful to mingle multiple            
> users' problems in one bug report.                                            
                                                                                
I'm not sure what to tell you about it not being repeatable on Windows, as      
I don't use it. But I think it would be silly to restrict debugging efforts     
to only those that can be repeated in Microsoft operating systems, 
especially since it may well turn out to be a VM system issue. 
I agree that this particular bug report has degenerated into nonsense and
I'll be leaving it alone henceforth.                                            

> [ ... ] you just want to whine                                                
> about how horrible Ubuntu or Linux is, then keep on doing what you're         
> doing here.   It's not going to lead to anything useful though.   But if      
                                                                                
Maybe you're mistaking me for someone else. I haven't engaged in any            
bashing of Ubuntu or Linux. Fwiw i've commercially deployed thousands of        
Ubuntu systems with great success.                                                                
                                                                                
oao,                                                                            
eric