Further apply read-only txn hints (#529)

* fix: Apply read-only txn hint when reading allowed docker registry info
* fix: Apply the readonly attribute to more transactions
* fix: Restore skipped lint checks due to old flake8/mypy no longer used

changes/529.fix.md

@@ -0,0 +1 @@
+Apply "read-only" attribute to a broader range of database transactions to improve overall performance

src/ai/backend/manager/api/auth.py

@@ -17,6 +17,7 @@
 from aiohttp import web
 import aiohttp_cors
 from aioredis import Redis
+from aioredis.client import Pipeline as RedisPipeline
 from dateutil.tz import tzutc
 from dateutil.parser import parse as dtparse
 import sqlalchemy as sa
@@ -437,12 +438,12 @@ async def _query_cred():
             if row is None:
                 raise AuthorizationFailed('Access key not found')
 
-            async def _pipe_builder(r: Redis):
+            async def _pipe_builder(r: Redis) -> RedisPipeline:
                 pipe = r.pipeline()
                 num_queries_key = f'kp:{access_key}:num_queries'
                 pipe.incr(num_queries_key)
                 pipe.expire(num_queries_key, 86400 * 30)  # retention: 1 month
-                await pipe.execute()
+                return pipe
 
             await redis.execute(root_ctx.redis_stat, _pipe_builder)
         else:
@@ -482,12 +483,12 @@ async def _query_cred():
             if not secrets.compare_digest(my_signature, signature):
                 raise AuthorizationFailed('Signature mismatch')
 
-            async def _pipe_builder(r: Redis):
+            async def _pipe_builder(r: Redis) -> RedisPipeline:
                 pipe = r.pipeline()
                 num_queries_key = f'kp:{access_key}:num_queries'
                 pipe.incr(num_queries_key)
                 pipe.expire(num_queries_key, 86400 * 30)  # retention: 1 month
-                await pipe.execute()
+                return pipe
 
             await redis.execute(root_ctx.redis_stat, _pipe_builder)
         else:

src/ai/backend/manager/api/events.py

@@ -104,7 +104,7 @@ async def push_session_events(
     if group_name == '*':
         group_id = '*'
     else:
-        async with root_ctx.db.begin() as conn:
+        async with root_ctx.db.begin_readonly() as conn:
             query = (
                 sa.select([groups.c.id])
                 .select_from(groups)

src/ai/backend/manager/api/resource.py

@@ -507,7 +507,7 @@ async def get_time_binned_monthly_stats(request: web.Request, user_uuid=None):
     now = datetime.now(tzutc())
     start_date = now - timedelta(days=30)
     root_ctx: RootContext = request.app['_root.context']
-    async with root_ctx.db.begin() as conn:
+    async with root_ctx.db.begin_readonly() as conn:
         query = (
             sa.select([kernels])
             .select_from(kernels)