Configuration

SAGE-Viewer reads all simulation parameters directly from the SAGE .par file. No separate config file is needed.

CLI options

Option	Default	Description
--par FILE	(required)	Path to SAGE .par file
--snap N	last snap	Initial snapshot number
--port N	8080	Trame server port
--n-jobs N	CPUs-1	Parallel workers for halo loading
--min-halo-mass MSUN	1e10	Minimum halo mass floor (Msun)
--min-stellar-mass MSUN	1e8	Minimum stellar mass floor (Msun)
--max-halos N	100000	Downsample ceiling for haloes per snapshot
--max-galaxies N	100000	Downsample ceiling for galaxies per snapshot

Par file fields used

SAGE-Viewer reads the following fields from the .par file:

Field	Used for
OutputDir	Locating SAGE HDF5 galaxy output
FileNameGalaxies	Galaxy output file base name
FirstFile / LastFile	Range of tree files to read
SimulationDir	Directory containing lhalo_binary tree files
TreeName	Base name of tree files (e.g. trees_063)
FileWithSnapList	Scale factor list file
LastSnapShotNr	Number of snapshots
Hubble_h	Unit conversion
BoxSize	Camera framing and zoom-to-box

Performance tuning

For interactive use on a laptop with miniMillennium:

sage-viewer --par input/millennium.par \
  --max-halos 30000 \
  --max-galaxies 30000 \
  --min-halo-mass 1e11 \
  --n-jobs 4

For cluster use with full data:

sage-viewer --par input/millennium.par \
  --max-halos 100000 \
  --n-jobs 16 \
  --port 8080