Add memory profiling tests.

docs/dev/NOTES.md

@@ -0,0 +1,32 @@
+# Performance test data
+
+VMWare running ArchLinux on MacBook Pro, 4-core Intel(R) Core(TM) i7-1068NG7
+CPU @ 2.30GHz, 8Gb RAM, SSD
+
+Decode
+LoC Children's Subjects SKOS/RDF
+[NT](https://id.loc.gov/download/authorities/childrensSubjects.skosrdf.nt.gz)
+and
+[TTL](https://id.loc.gov/download/authorities/childrensSubjects.skosrdf.ttl.gz)
+(379,163 triples):
+
+NT format: 19s
+TTL format: 25s
+
+Decode LoC Subject Headings (10,116,071 triples)
+
+NT: 8'33"
+TTL: 11'4"
+
+TTL takes 29%-31% longer than NT.
+
+Script (replace `<file path>` and `<format>` accordingly):
+
+```
+from lsup_rdf import env_init
+from lsup_rdf.graph import Graph
+
+env_init()
+with open("<file path>") as fh:
+    gr = Graph.from_rdf(fh, "<format>")
+```