The still render measures the time from when the render is initiated to the 
time when the render completes.  In client/server mode, this can include 
communication and parallel overhead costs.

ParaView has two types of renders: still render and interactive render.  
Interactive renders occur while you are interacting with the 3D view by moving 
the mouse.  It tries to maintain interactive rendering rates.  Still renders 
happen after interaction stops to give a full resolution view of your data.

The vtkMPIMoveData filter is a special filter that collects poly data on the 
server and pushes it to the client.  ParaView settings determine when this 
happens.  Generally when the size of the data is below a certain threshold, 
then ParaView will push the data to the client.

-Ken


On 9/30/09 5:11 AM, "chew ping" <[email protected]> wrote:

Dear Ken,

thanks for the reply. i have one more question to ask.
in the timer log, the first 3 lines:

--------------------------------------------------
Local Process
Still Render, 3.029 seconds
Execute vtkMPIMoveData id: 457, 1.98248 seconds
--------------------------------------------------

does these mean that, at the client's end, it took 3.029 seconds to renders the 
geometry send back from process 0?
what does still render means? how about the third line? after still render, why 
does the MPI need to move data? which data? to where?

i tried running the same data using np1 until np10, and i get the following 
reading for still render, the rest of the readings are quite consistent, which 
makes me wonder why the time (still render) decrease initially but increase 
eventually? shouldn't it become much faster when more nodes are used? all my 
server nodes are identical to each other (intel core 2 duo, 2.66 GHz)


----------------------------------------------
number of process used still render (seconds)
np1 7.16043
np2 3.93390
np3 3.05784
np4 3.02900
np5 3.02851
np6 3.04962
np7 3.43479
np8 3.47883
np9 3.71554
np10 3.80835
----------------------------------------------


appreciate your reply!

regards,
chewping


________________________________
From: [email protected]
To: [email protected]; [email protected]
CC: [email protected]
Date: Mon, 28 Sep 2009 08:37:08 -0600
Subject: Re: [Paraview] How to interpret timer log

Re: [Paraview] How to interpret timer log Both scenarios are wrong.  ParaView 
will not push out data from process 0 to processes 1-3 unless you explicitly 
run a filter that does that (or the reader does that internally, but I know of 
no such reader).  What is actually happening is more along the lines of:


 1.  Processes 0-3 each read in a partition of data from the file.
 2.  Each process extracts polygonal geometry from their local data.
 3.  Per your settings, ParaView decides to send the geometry to the client.  
The data is collected to process 0 and sent to the client.

The reason you are not seeing vtkFileSeriesReader on all of the servers is that 
there is a threshold in the timer log to not show anything that executes under 
a certain amount of time (by default 0.01 seconds).  If you change the Time 
Threshold to Show All, you should be able to see everything that executes, even 
if it completes immediately.

You should note that how readers read partitions is determined by the reader 
itself.  Many of the readers do not really handle partitioned reading.  Thus, 
the reader will do something naïve like read everything on process 0.  Based on 
your timings, that is probably what is happening to you.  That is, processes 
1-3 probably have empty data.  You never specified what format of data you are 
reader, so I cannot answer the data completely.  However, if you want to know 
how your data is partitioned on the server (at least, before rendering), you 
can run the Process Ids filter.

-Ken


On 9/24/09 9:09 PM, "chew ping" <[email protected] <http://msn.com> > wrote:

Hi all,

I'm doing parallel rendering using 1 client (dual core laptop) and 2 cluster 
servers (dual core desktop)
below is the timer log result i collected when i run: mpirun -np 4 pvserver

-----------------------------------------------------------------------------------------------
Local Process
Still Render, 3.029 seconds
Execute vtkMPIMoveData id: 457, 1.98248 seconds


Server, Process 0
Execute vtkFileSeriesReader id: 176, 0.637821 seconds
Execute vtkMPIMoveData id: 457, 1.49186 seconds
Dataserver gathering to 0, 0.829525 seconds
Dataserver sending to client, 0.661658 seconds

Server, Process 1
Execute vtkMPIMoveData id: 457, 0.141821 seconds
Dataserver gathering to 0, 0.141544 seconds

Server, Process 2
Execute vtkMPIMoveData id: 457, 0.243584 seconds
Dataserver gathering to 0, 0.243318 seconds

Server, Process 3
Execute vtkMPIMoveData id: 457, 0.191589 seconds
Dataserver gathering to 0, 0.191303 seconds

-----------------------------------------------------------------------------------------------------

i have difficulty interpreting the timer log, my guess is:

Scenario 1:
Process 0 reads the whole data, disseminate the dats into 4 pieces, then 
distribute to itself and Process 1&2&3,
each node will process the data and send it back Process 0,
Process 0 gather all data and send it back to client,
client renders the data

Scenario 2:
Process 0 reads the whole data, distribute the whole data to Process 0&1&2&3,
each node will 'take' their own piece of data to process, then send it back 
Process 0,
Process 0 gather all data and send it back to client,
client renders the data

Which scenario is the correct one? or both are wrong?

is there any resources i could refer to find what does it mean by: Execute 
vtkFileSeriesReader, Execute vtkMPIMoveData?

any help / feedback is highly appreciated!
thanks!

regards,
chewping







   ****      Kenneth Moreland
    ***      Sandia National Laboratories
***********
*** *** ***  email: [email protected] <http://sandia.gov>
**  ***  **  phone: (505) 844-8919
    ***      web:   http://www.cs.unm.edu/~kmorel 
<http://www.cs.unm.edu/%7Ekmorel>




   ****      Kenneth Moreland
    ***      Sandia National Laboratories
***********
*** *** ***  email: [email protected]
**  ***  **  phone: (505) 844-8919
    ***      web:   http://www.cs.unm.edu/~kmorel

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