Maximum LCIO event size / file size of 4 GB?

[alexandertuna]

Hi LCIOers,

Do you know if there's a maximum file/event size of 4 GB? I am generating some muon collider events with a large background, and I noticed things start to break when the event size (I have one event per file) surpasses 4-ish GB:

Singularity> du -hs neutrinoGun_digi_3900MB.slcio neutrinoGun_digi_4200MB.slcio
3.9G	neutrinoGun_digi_3900MB.slcio
4.2G	neutrinoGun_digi_4200MB.slcio
Singularity>
Singularity> lcio_event_counter neutrinoGun_digi_3900MB.slcio
1
Singularity> lcio_event_counter neutrinoGun_digi_4200MB.slcio
1
Singularity> lcio_check_col_elements MCParticle neutrinoGun_digi_3900MB.slcio
 found 1 MCParticle element(s) in 1 event(s)
 [ blah blah ]
Singularity> lcio_check_col_elements MCParticle neutrinoGun_digi_4200MB.slcio
terminate called after throwing an instance of 'sio::exception'
  what():  /tmp/root/spack-stage/spack-stage-sio-0.2-2n4u2dalexze6gcn7qhp5buf5kc6kkdo/spack-src/source/src/io_device.cc (l.34) in seek: Can't seek device cursor: out of range! [out_of_range]
/tmp/root/spack-stage/spack-stage-lcio-2.22.5-jygurrobznbsj3xhqvkxva4ariufnr2c/spack-src/src/cpp/src/MT/LCReader.cc (l.201) in readNextEvent: Couldn't read next event! [out_of_range]
Aborted (core dumped)
Singularity>

Maybe this is related to #71 but I'm not sure

Thanks for any insight!
Alex

[tmadlener]

Did the writing of the event work without issues? If that is the case this might be related to #71 but it seems to be a different issue, as that happens during output, but you seem to be running into issues while reading. It would be interesting to step through the whole thing with a debugger to see what pos and _buffer.size() report here:

https://github.com/iLCSoft/SIO/blob/9368e91bb3f4a99e8286d26dc7a425f216ff97d7/source/src/io_device.cc#L33