use ujson to load ticker files 30% faster from disk.

freqtrade/optimize/__init__.py

@@ -10,9 +10,16 @@ import arrow
 from freqtrade import misc, constants, OperationalException
 from freqtrade.exchange import Exchange
 from freqtrade.arguments import TimeRange
+import importlib
+ujson_found = importlib.util.find_spec("ujson")
+if ujson_found is not None:
+    import ujson
 
 logger = logging.getLogger(__name__)
 
+if ujson_found is not None:
+    logger.debug('Loaded UltraJson ujson in optimize.py')
+
 
 def trim_tickerlist(tickerlist: List[Dict], timerange: TimeRange) -> List[Dict]:
     if not tickerlist:
@@ -63,11 +70,17 @@ def load_tickerdata_file(
     if os.path.isfile(gzipfile):
         logger.debug('Loading ticker data from file %s', gzipfile)
         with gzip.open(gzipfile) as tickerdata:
-            pairdata = json.load(tickerdata)
+            if ujson_found is not None:
+                pairdata = ujson.load(tickerdata, precise_float=True)
+            else:
+                pairdata = json.load(tickerdata)
     elif os.path.isfile(file):
         logger.debug('Loading ticker data from file %s', file)
         with open(file) as tickerdata:
-            pairdata = json.load(tickerdata)
+            if ujson_found is not None:
+                pairdata = ujson.load(tickerdata, precise_float=True)
+            else:
+                pairdata = json.load(tickerdata)
     else:
         return None
 
@@ -163,7 +176,10 @@ def load_cached_data_for_updating(filename: str,
     # read the cached file
     if os.path.isfile(filename):
         with open(filename, "rt") as file:
-            data = json.load(file)
+            if ujson_found is not None:
+                data = ujson.load(file, precise_float=True)
+            else:
+                data = json.load(file)
             # remove the last item, because we are not sure if it is correct
             # it could be fetched when the candle was incompleted
             if data:
@@ -226,4 +242,4 @@ def download_backtesting_testdata(datadir: str,
     logger.debug("New Start: %s", misc.format_ms_time(data[0][0]))
     logger.debug("New End: %s", misc.format_ms_time(data[-1][0]))
 
-    misc.file_dump_json(filename, data)
+    misc.file_dump_json(filename, data)

requirements.txt

@@ -23,3 +23,10 @@ scikit-optimize==0.5.2
 
 # Required for plotting data
 #plotly==3.0.0
+
+# find first, C search in arrays
+py_find_1st==1.1.1
+
+#Load ticker files 30% faster
+ujson==1.35
+