Pelegant I/O issue for CSRDRIFT element

[GPenn]

I have been trying out the CSRCSBEND and CSRDRIFT elements. They usually work great, but there is one corner case where Pelegant running on multiple nodes (not just multiple processes) has a problem writing the output file for a CSRDRIFT element specified through STUPAKOV_OUTPUT.

It seems that the first node gets to write its data, but the others cannot handle the locked file. The problem does not occur with CSRCSBEND elements. I compiled the code from source, so there might be some issue there, but it is surprising that the two CSR elements would have different behavior. I have not seen this issue come up for any other element.

The error message I get is:

Error:
unable to open file CSR.L2.csr for writing--file is locked (SDDS_InitializeOutput)
Problem setting up output file for CSRDRIFT (Stupakov mode)

A basic pair of files is attached. This is for version 2023.3.0, on a linux machine.

Cheers,
Gregg

[michael_borland]

Gregg,

Unfortunately, that feature is not supported for the parallel version, although you have no way to know that from the manual. Those messages indicate that each processor is trying to open the same file, and failing.

I'll put it on my to-do list to provide parallel support, although I wouldn't recommend it for production runs as it will slow things.

--Michael

[GPenn]

Thank you for looking into this, Michael. For now I am doing minimal serial runs when I want to look at the drift CSR.