# pvserver and stream tracer
**URL:** https://discourse.paraview.org/t/pvserver-and-stream-tracer/14580
**Category:** ParaView Support
**Created:** [May 7, 2024, 9:54pm UTC](https://discourse.paraview.org/t/pvserver-and-stream-tracer/14580 "2024-05-07T21:54:46Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@MarkY](https://discourse.paraview.org/u/MarkY)
#### Post date: [May 7, 2024, 9:54pm UTC](https://discourse.paraview.org/t/pvserver-and-stream-tracer/14580/1 "2024-05-07T21:54:47Z")
Hello. When I run paraview connected to a locally running pvserver (so that I can do things faster) run with:
mpirun -np 4 pvserver &
The server crashes when I try to run stream tracer with a spherical point cloud seed source.
The error that paraview puts out is:
The errors spat out by pvserver are given in this log file:
[pvserver.error.log](https://discourse.paraview.org/uploads/short-url/lVWU957FjuunXA1jAz14DL4KNE7.log) (37.1 KB)
And the errors spat out by paraview to the command prompt that it was run from are given in this log file:
[paraview.error.log](https://discourse.paraview.org/uploads/short-url/wrsmdEJ1a6claK868YCHOGV2vRh.log) (1.6 KB)
I found this prior post that seems to deal with this issue but my understanding is that it requires running commands as a python script?
> [@stream tracer with custom fails in parallel](https://discourse.paraview.org/t/stream-tracer-with-custom-fails-in-parallel/672):
>
> Hi, I am trying to create a stream tracer with custom source on a decomposed OpenFOAM case with pvbatch in parallel. The job exits with an MPI Error, see attached logfile. [pvbatch.log](https://discourse.paraview.org/uploads/default/original/1X/a4f9d6220a8c6e64e8d56c0478cb425f0c64b1bb.log) (1.8 KB) Running pvbatch in serial works fine. Increasing OnRatio of maksPoints filter to some high values helps, but then unfortunately the streamline distribution is too coarse. I played around with Sampling Mode of maskPoints, but so far did not find any working solution. Does anybody have an idea? Attached …
I am wondering if there is a way to replace or alias or attach an additional bit of code to the standard tracer command in the paraview interface with a custom commands that use the: AppendReduce class? as mentioned above so it does not crash? Is there a way to just issue the commands for the stream tracer in the python shell? Should I just record what I normally do when running locally not connected (single core) and then modify this with AppendReduce? How might I use AppendReduce? Is there anyway to get a python script from the state file that I have saved that includes this stream tracer? I looked at the AppendReduce page here:
[https://kitware.github.io/paraview-docs/v5.9.0/python/paraview.simple.AppendReduce.html](https://kitware.github.io/paraview-docs/v5.9.0/python/paraview.simple.AppendReduce.html)
It’s not ringing any bells for me. How would I use this with Tracer?
I am currently running paraview 5.11.
Kind regards,
Mark
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### Author:  [@MarkY](https://discourse.paraview.org/u/MarkY)
#### Post date: [May 9, 2024, 2:25am UTC](https://discourse.paraview.org/t/pvserver-and-stream-tracer/14580/2 "2024-05-09T02:25:45Z")
Never mind. I just discovered that this has effectively been done for latest version.
Kind regards,
Mark