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@wseaton
Created October 30, 2023 14:40
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import json
import graphviz
import trino
import os
import sys
import logging
import concurrent.futures
from concurrent.futures import ThreadPoolExecutor
from cachier import cachier
import datetime
logging.basicConfig(stream=sys.stdout, level=logging.DEBUG)
logger = logging.getLogger("trino")
logger.setLevel(logging.DEBUG)
def create_trino_connection():
return trino.dbapi.connect(
host=os.getenv("STARBURST_HOST"),
port=443,
http_scheme="https",
verify=True,
user=os.getenv("STARBURST_DEV_USER"),
auth=trino.auth.OAuth2Authentication(),
)
def read_manifest(file_path):
with open(file_path, 'r') as f:
return json.load(f)
def build_graphviz_graph(manifest, previous_stages_dict):
dot = graphviz.Digraph(comment='DBT Models')
dot.graph_attr['rankdir'] = 'LR'
threshold = 10.0 # Set your threshold value
if os.path.exists('results.tsv'):
os.remove('results.tsv')
with open('results.tsv', 'w') as f:
f.write('node_name\tstages\n')
with ThreadPoolExecutor(max_workers=4) as executor:
futures = {executor.submit(get_query_stages, node_name, node_data['compiled_code']): node_name for node_name, node_data in manifest['nodes'].items() if node_data['compiled_code'] and not node_name.startswith('test.')}
for future in futures:
node_name, stages = future.result()
f.write(f"{node_name}\t{stages}\n")
# Check for high relative increase in stages
dependencies = manifest['nodes'][node_name].get('depends_on', {}).get('nodes', [])
input_stages = [previous_stages_dict.get(dep, 0) for dep in dependencies]
if input_stages:
avg_input_stages = sum(input_stages) / len(input_stages)
if avg_input_stages > 0 and stages / avg_input_stages >= threshold: # Check for non-zero
dot.node(node_name, f"{node_name.split('.')[-1]}\n{stages} stages", style="filled", fillcolor="red")
else:
dot.node(node_name, f"{node_name.split('.')[-1]}\n{stages} stages")
else:
dot.node(node_name, f"{node_name.split('.')[-1]}\n{stages} stages")
for dep in dependencies:
dot.edge(dep, node_name)
previous_stages_dict[node_name] = stages
return dot
@cachier(stale_after=datetime.timedelta(minutes=60))
def get_plan(node_name, sql):
# remove ; from any part of the statement
sql = sql.replace(';', '')
cur = create_trino_connection().cursor()
cur.execute(f"EXPLAIN (TYPE DISTRIBUTED, FORMAT JSON) {sql}")
row = cur.fetchone()
explain_json = json.loads(row[0])
cur.close()
return explain_json
def get_query_stages(node_name, sql):
stages = count_stages_in_query_plan(get_plan(node_name, sql))
return node_name, stages
def is_virtual_stage(stage):
# Check for 'estimates' key in the stage
estimates_list = stage.get('estimates', [])
for estimates in estimates_list:
# Check for 'NaN' or 0.0 in relevant fields
if not (
estimates.get('outputSizeInBytes', 'NaN') == 'NaN' and
estimates.get('cpuCost', 'NaN') == 'NaN' and
estimates.get('memoryCost', 0.0) == 0.0 and
estimates.get('networkCost', 0.0) == 0.0
):
return False
return True
def count_stages_in_query_plan(query_plan):
stage_count = 0
if isinstance(query_plan, dict):
# If this stage is "virtual" (has no cost), do not count it
if not is_virtual_stage(query_plan):
stage_count += 1
for key, value in query_plan.items():
if isinstance(value, dict):
# Count this as a stage and explore its children
stage_count += count_stages_in_query_plan(value)
elif isinstance(value, list):
for item in value:
if isinstance(item, dict):
stage_count += count_stages_in_query_plan(item)
else:
print(f"Warning: Unexpected non-dict value encountered for stage {key}: {value}")
return stage_count
if __name__ == "__main__":
manifest_file_path = "./target/manifest.json"
manifest = read_manifest(manifest_file_path)
previous_stages_dict = {}
dot = build_graphviz_graph(manifest, previous_stages_dict)
# save dotfile to disk
dot.save('output.dot')
dot.render('output', view=True, format='png')
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