Fix synthetic graph generation instructions

- Correct path to GAPBS reference converter tool (bench/gapbs-reference/)
- Use -e flag for edge list output (compatible with NWGraph)
- Add note about using smaller scale for test graphs
- Update download script warning messages

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: lums658

doc-src/sphinx/userguide/benchmarking.rst

@@ -182,38 +182,51 @@ Kron (GAP-kron)
 
 :Source: Generated using Graph 500 Kronecker generator
 :Parameters: Scale 27, edge factor 16 (``-g27 -k16``)
-:Format: Generated directly to binary
+:Format: Edge list or serialized binary
 :Type: Undirected, unweighted
 :Characteristics:
    - Scale-free degree distribution
    - Small-world properties
    - Self-similar structure
    - Synthetic but realistic
 
-Generate with the GAPBS converter:
+Generate using the GAPBS reference ``converter`` tool (included in
+``bench/gapbs-reference/``):
 
 .. code-block:: bash
 
-   ./converter -g27 -k16 -b kron.sg
+   # Generate Kronecker graph as edge list (for NWGraph)
+   ./bench/gapbs-reference/converter -g27 -k16 -e kron.el
+
+   # Or generate as GAPBS serialized format
+   ./bench/gapbs-reference/converter -g27 -k16 -b kron.sg
+
+For smaller test graphs, use a lower scale (e.g., ``-g20`` for ~1M vertices).
 
 Urand (GAP-urand)
 ~~~~~~~~~~~~~~~~~
 
 :Source: Generated using Erdos-Renyi random generator
 :Parameters: 2^27 vertices, degree 16 (``-u27 -k16``)
-:Format: Generated directly to binary
+:Format: Edge list or serialized binary
 :Type: Undirected, unweighted
 :Characteristics:
    - Uniform random edge placement
    - Worst-case memory locality
    - No clustering structure
    - Binomial degree distribution around 16
 
-Generate with the GAPBS converter:
+Generate using the GAPBS reference ``converter`` tool:
 
 .. code-block:: bash
 
-   ./converter -u27 -k16 -b urand.sg
+   # Generate uniform random graph as edge list (for NWGraph)
+   ./bench/gapbs-reference/converter -u27 -k16 -e urand.el
+
+   # Or generate as GAPBS serialized format
+   ./bench/gapbs-reference/converter -u27 -k16 -b urand.sg
+
+For smaller test graphs, use a lower scale (e.g., ``-u20`` for ~1M vertices).
 
 Downloading Graphs
 ==================

scripts/download_gap_graphs.sh

@@ -307,8 +307,10 @@ while [[ $# -gt 0 ]]; do
             ;;
         kron|urand)
             warn "Synthetic graph '$1' must be generated, not downloaded."
-            warn "Use: ./converter -g27 -k16 -b kron.sg (for kron)"
-            warn "Use: ./converter -u27 -k16 -b urand.sg (for urand)"
+            warn "Use the GAPBS reference converter tool:"
+            warn "  ./bench/gapbs-reference/converter -g27 -k16 -e kron.el   (for kron)"
+            warn "  ./bench/gapbs-reference/converter -u27 -k16 -e urand.el  (for urand)"
+            warn "For smaller graphs, use lower scale (e.g., -g20 for ~1M vertices)"
             shift
             ;;
         *)