perf: make ListAIBridgeSessions 10x faster (#23774)

_Disclaimer: produced using Claude Opus 4.6, reviewed by me, and
validated against Dogfood dataset._

The `ListAIBridgeSessions` query materialized and aggregated all
matching interceptions before paginating, then ran expensive
token/prompt lookups across the full dataset. For a page of 25 sessions
against ~200k interceptions (our dogfood dataset), this meant:
- Three CTEs scanning all rows (filtered_interceptions, session_tokens,
session_root)
  - ARRAY_AGG(fi.id) collecting every interception ID per session
- Lateral prompt lookup via ANY(array_of_all_ids) running for every
session, not just the page
  - ~90MB of disk sorts and JIT compilation kicking in

The improvement is to restructure to paginate first and enrich after: a
single CTE groups interceptions into sessions with only cheap aggregates
(MIN, MAX, COUNT), applies cursor pagination and LIMIT, then lateral
joins fetch metadata, tokens, and prompts for just the ~25-row page.

  Measured against 220k interceptions / 160k sessions:

  | Metric             | Before | After |
  |--------------------|--------|-------|
  | Execution time     | 1800ms | 185ms |
  | Shared buffer hits | 737k   | 2.6k  |
  | Disk sort spill    | 86MB   | 16MB  |
  | Lateral loops      | 160k   | 25    |

https://grafana.dev.coder.com/goto/fbODPGtvR?orgId=1 the results are
identical, just _much_ faster.

--- 

Also includes some additional tests which I added prior to refactoring
the query to ensure no regressions on edge-cases.

---------

Signed-off-by: Danny Kopping <danny@coder.com>
This commit is contained in:
Danny Kopping
2026-03-31 14:42:23 +02:00
committed by GitHub
parent acd2ff63a7
commit 9fa103929a
5 changed files with 463 additions and 165 deletions
+2 -2
View File
@@ -996,8 +996,6 @@ func (q *sqlQuerier) ListAuthorizedAIBridgeSessions(ctx context.Context, arg Lis
query := fmt.Sprintf("-- name: ListAuthorizedAIBridgeSessions :many\n%s", filtered)
rows, err := q.db.QueryContext(ctx, query,
arg.AfterSessionID,
arg.Offset,
arg.Limit,
arg.StartedAfter,
arg.StartedBefore,
arg.InitiatorID,
@@ -1005,6 +1003,8 @@ func (q *sqlQuerier) ListAuthorizedAIBridgeSessions(ctx context.Context, arg Lis
arg.Model,
arg.Client,
arg.SessionID,
arg.Offset,
arg.Limit,
)
if err != nil {
return nil, err
+4
View File
@@ -788,6 +788,10 @@ type sqlcQuerier interface {
// Returns paginated sessions with aggregated metadata, token counts, and
// the most recent user prompt. A "session" is a logical grouping of
// interceptions that share the same session_id (set by the client).
//
// Pagination-first strategy: identify the page of sessions cheaply via a
// single GROUP BY scan, then do expensive lateral joins (tokens, prompts,
// first-interception metadata) only for the ~page-size result set.
ListAIBridgeSessions(ctx context.Context, arg ListAIBridgeSessionsParams) ([]ListAIBridgeSessionsRow, error)
ListAIBridgeTokenUsagesByInterceptionIDs(ctx context.Context, interceptionIds []uuid.UUID) ([]AIBridgeTokenUsage, error)
ListAIBridgeToolUsagesByInterceptionIDs(ctx context.Context, interceptionIds []uuid.UUID) ([]AIBridgeToolUsage, error)
+82 -83
View File
@@ -1347,95 +1347,87 @@ func (q *sqlQuerier) ListAIBridgeSessionThreads(ctx context.Context, arg ListAIB
}
const listAIBridgeSessions = `-- name: ListAIBridgeSessions :many
WITH filtered_interceptions AS (
WITH cursor_pos AS (
-- Resolve the cursor's started_at once, outside the HAVING clause,
-- so the planner cannot accidentally re-evaluate it per group.
SELECT MIN(aibridge_interceptions.started_at) AS started_at
FROM aibridge_interceptions
WHERE aibridge_interceptions.session_id = $1 AND aibridge_interceptions.ended_at IS NOT NULL
),
session_page AS (
-- Paginate at the session level first; only cheap aggregates here.
SELECT
aibridge_interceptions.id, aibridge_interceptions.initiator_id, aibridge_interceptions.provider, aibridge_interceptions.model, aibridge_interceptions.started_at, aibridge_interceptions.metadata, aibridge_interceptions.ended_at, aibridge_interceptions.api_key_id, aibridge_interceptions.client, aibridge_interceptions.thread_parent_id, aibridge_interceptions.thread_root_id, aibridge_interceptions.client_session_id, aibridge_interceptions.session_id
ai.session_id,
ai.initiator_id,
MIN(ai.started_at) AS started_at,
MAX(ai.ended_at) AS ended_at,
COUNT(*) FILTER (WHERE ai.thread_root_id IS NULL) AS threads
FROM
aibridge_interceptions
aibridge_interceptions ai
WHERE
-- Remove inflight interceptions (ones which lack an ended_at value).
aibridge_interceptions.ended_at IS NOT NULL
ai.ended_at IS NOT NULL
-- Filter by time frame
AND CASE
WHEN $4::timestamptz != '0001-01-01 00:00:00+00'::timestamptz THEN aibridge_interceptions.started_at >= $4::timestamptz
WHEN $2::timestamptz != '0001-01-01 00:00:00+00'::timestamptz THEN ai.started_at >= $2::timestamptz
ELSE true
END
AND CASE
WHEN $5::timestamptz != '0001-01-01 00:00:00+00'::timestamptz THEN aibridge_interceptions.started_at <= $5::timestamptz
WHEN $3::timestamptz != '0001-01-01 00:00:00+00'::timestamptz THEN ai.started_at <= $3::timestamptz
ELSE true
END
-- Filter initiator_id
AND CASE
WHEN $6::uuid != '00000000-0000-0000-0000-000000000000'::uuid THEN aibridge_interceptions.initiator_id = $6::uuid
WHEN $4::uuid != '00000000-0000-0000-0000-000000000000'::uuid THEN ai.initiator_id = $4::uuid
ELSE true
END
-- Filter provider
AND CASE
WHEN $7::text != '' THEN aibridge_interceptions.provider = $7::text
WHEN $5::text != '' THEN ai.provider = $5::text
ELSE true
END
-- Filter model
AND CASE
WHEN $8::text != '' THEN aibridge_interceptions.model = $8::text
WHEN $6::text != '' THEN ai.model = $6::text
ELSE true
END
-- Filter client
AND CASE
WHEN $9::text != '' THEN COALESCE(aibridge_interceptions.client, 'Unknown') = $9::text
WHEN $7::text != '' THEN COALESCE(ai.client, 'Unknown') = $7::text
ELSE true
END
-- Filter session_id
AND CASE
WHEN $10::text != '' THEN aibridge_interceptions.session_id = $10::text
WHEN $8::text != '' THEN ai.session_id = $8::text
ELSE true
END
-- Authorize Filter clause will be injected below in ListAuthorizedAIBridgeSessions
-- @authorize_filter
),
session_tokens AS (
-- Aggregate token usage across all interceptions in each session.
-- Group by (session_id, initiator_id) to avoid merging sessions from
-- different users who happen to share the same client_session_id.
SELECT
fi.session_id,
fi.initiator_id,
COALESCE(SUM(tu.input_tokens), 0)::bigint AS input_tokens,
COALESCE(SUM(tu.output_tokens), 0)::bigint AS output_tokens
-- TODO: add extra token types once https://github.com/coder/aibridge/issues/150 lands.
FROM
filtered_interceptions fi
LEFT JOIN
aibridge_token_usages tu ON fi.id = tu.interception_id
GROUP BY
fi.session_id, fi.initiator_id
),
session_root AS (
-- Build one summary row per session. Group by (session_id, initiator_id)
-- to avoid merging sessions from different users who happen to share the
-- same client_session_id. The ARRAY_AGG with ORDER BY picks values from
-- the chronologically first interception for fields that should represent
-- the session as a whole (client, metadata). Threads are counted as
-- distinct root interception IDs: an interception with a NULL
-- thread_root_id is itself a thread root.
SELECT
fi.session_id,
fi.initiator_id,
(ARRAY_AGG(fi.client ORDER BY fi.started_at, fi.id))[1] AS client,
(ARRAY_AGG(fi.metadata ORDER BY fi.started_at, fi.id))[1] AS metadata,
ARRAY_AGG(DISTINCT fi.provider ORDER BY fi.provider) AS providers,
ARRAY_AGG(DISTINCT fi.model ORDER BY fi.model) AS models,
MIN(fi.started_at) AS started_at,
MAX(fi.ended_at) AS ended_at,
COUNT(DISTINCT COALESCE(fi.thread_root_id, fi.id)) AS threads,
-- Collect IDs for lateral prompt lookup.
ARRAY_AGG(fi.id) AS interception_ids
FROM
filtered_interceptions fi
GROUP BY
fi.session_id, fi.initiator_id
ai.session_id, ai.initiator_id
HAVING
-- Cursor pagination: uses a composite (started_at, session_id)
-- cursor to support keyset pagination. The less-than comparison
-- matches the DESC sort order so rows after the cursor come
-- later in results. The cursor value comes from cursor_pos to
-- guarantee single evaluation.
CASE
WHEN $1::text != '' THEN (
(MIN(ai.started_at), ai.session_id) < (
(SELECT started_at FROM cursor_pos),
$1::text
)
)
ELSE true
END
ORDER BY
MIN(ai.started_at) DESC,
ai.session_id DESC
LIMIT COALESCE(NULLIF($10::integer, 0), 100)
OFFSET $9
)
SELECT
sr.session_id,
sp.session_id,
visible_users.id AS user_id,
visible_users.username AS user_username,
visible_users.name AS user_name,
@@ -1444,51 +1436,52 @@ SELECT
sr.models::text[] AS models,
COALESCE(sr.client, '')::varchar(64) AS client,
sr.metadata::jsonb AS metadata,
sr.started_at::timestamptz AS started_at,
sr.ended_at::timestamptz AS ended_at,
sr.threads,
sp.started_at::timestamptz AS started_at,
sp.ended_at::timestamptz AS ended_at,
sp.threads,
COALESCE(st.input_tokens, 0)::bigint AS input_tokens,
COALESCE(st.output_tokens, 0)::bigint AS output_tokens,
COALESCE(slp.prompt, '') AS last_prompt
FROM
session_root sr
session_page sp
JOIN
visible_users ON visible_users.id = sr.initiator_id
LEFT JOIN
session_tokens st ON st.session_id = sr.session_id AND st.initiator_id = sr.initiator_id
visible_users ON visible_users.id = sp.initiator_id
LEFT JOIN LATERAL (
-- Lateral join to efficiently fetch only the most recent user prompt
-- across all interceptions in the session, avoiding a full aggregation.
SELECT
(ARRAY_AGG(ai.client ORDER BY ai.started_at, ai.id))[1] AS client,
(ARRAY_AGG(ai.metadata ORDER BY ai.started_at, ai.id))[1] AS metadata,
ARRAY_AGG(DISTINCT ai.provider ORDER BY ai.provider) AS providers,
ARRAY_AGG(DISTINCT ai.model ORDER BY ai.model) AS models,
ARRAY_AGG(ai.id) AS interception_ids
FROM aibridge_interceptions ai
WHERE ai.session_id = sp.session_id
AND ai.initiator_id = sp.initiator_id
AND ai.ended_at IS NOT NULL
) sr ON true
LEFT JOIN LATERAL (
-- Aggregate tokens only for this session's interceptions.
SELECT
COALESCE(SUM(tu.input_tokens), 0)::bigint AS input_tokens,
COALESCE(SUM(tu.output_tokens), 0)::bigint AS output_tokens
FROM aibridge_token_usages tu
WHERE tu.interception_id = ANY(sr.interception_ids)
) st ON true
LEFT JOIN LATERAL (
-- Fetch only the most recent user prompt across all interceptions
-- in the session.
SELECT up.prompt
FROM aibridge_user_prompts up
WHERE up.interception_id = ANY(sr.interception_ids)
ORDER BY up.created_at DESC, up.id DESC
LIMIT 1
) slp ON true
WHERE
-- Cursor pagination: uses a composite (started_at, session_id) cursor
-- to support keyset pagination. The less-than comparison matches the
-- DESC sort order so that rows after the cursor come later in results.
CASE
WHEN $1::text != '' THEN (
(sr.started_at, sr.session_id) < (
(SELECT started_at FROM session_root WHERE session_id = $1),
$1::text
)
)
ELSE true
END
ORDER BY
sr.started_at DESC,
sr.session_id DESC
LIMIT COALESCE(NULLIF($3::integer, 0), 100)
OFFSET $2
sp.started_at DESC,
sp.session_id DESC
`
type ListAIBridgeSessionsParams struct {
AfterSessionID string `db:"after_session_id" json:"after_session_id"`
Offset int32 `db:"offset_" json:"offset_"`
Limit int32 `db:"limit_" json:"limit_"`
StartedAfter time.Time `db:"started_after" json:"started_after"`
StartedBefore time.Time `db:"started_before" json:"started_before"`
InitiatorID uuid.UUID `db:"initiator_id" json:"initiator_id"`
@@ -1496,6 +1489,8 @@ type ListAIBridgeSessionsParams struct {
Model string `db:"model" json:"model"`
Client string `db:"client" json:"client"`
SessionID string `db:"session_id" json:"session_id"`
Offset int32 `db:"offset_" json:"offset_"`
Limit int32 `db:"limit_" json:"limit_"`
}
type ListAIBridgeSessionsRow struct {
@@ -1519,11 +1514,13 @@ type ListAIBridgeSessionsRow struct {
// Returns paginated sessions with aggregated metadata, token counts, and
// the most recent user prompt. A "session" is a logical grouping of
// interceptions that share the same session_id (set by the client).
//
// Pagination-first strategy: identify the page of sessions cheaply via a
// single GROUP BY scan, then do expensive lateral joins (tokens, prompts,
// first-interception metadata) only for the ~page-size result set.
func (q *sqlQuerier) ListAIBridgeSessions(ctx context.Context, arg ListAIBridgeSessionsParams) ([]ListAIBridgeSessionsRow, error) {
rows, err := q.db.QueryContext(ctx, listAIBridgeSessions,
arg.AfterSessionID,
arg.Offset,
arg.Limit,
arg.StartedAfter,
arg.StartedBefore,
arg.InitiatorID,
@@ -1531,6 +1528,8 @@ func (q *sqlQuerier) ListAIBridgeSessions(ctx context.Context, arg ListAIBridgeS
arg.Model,
arg.Client,
arg.SessionID,
arg.Offset,
arg.Limit,
)
if err != nil {
return nil, err
+78 -79
View File
@@ -454,95 +454,91 @@ WHERE
-- Returns paginated sessions with aggregated metadata, token counts, and
-- the most recent user prompt. A "session" is a logical grouping of
-- interceptions that share the same session_id (set by the client).
WITH filtered_interceptions AS (
--
-- Pagination-first strategy: identify the page of sessions cheaply via a
-- single GROUP BY scan, then do expensive lateral joins (tokens, prompts,
-- first-interception metadata) only for the ~page-size result set.
WITH cursor_pos AS (
-- Resolve the cursor's started_at once, outside the HAVING clause,
-- so the planner cannot accidentally re-evaluate it per group.
SELECT MIN(aibridge_interceptions.started_at) AS started_at
FROM aibridge_interceptions
WHERE aibridge_interceptions.session_id = @after_session_id AND aibridge_interceptions.ended_at IS NOT NULL
),
session_page AS (
-- Paginate at the session level first; only cheap aggregates here.
SELECT
aibridge_interceptions.*
ai.session_id,
ai.initiator_id,
MIN(ai.started_at) AS started_at,
MAX(ai.ended_at) AS ended_at,
COUNT(*) FILTER (WHERE ai.thread_root_id IS NULL) AS threads
FROM
aibridge_interceptions
aibridge_interceptions ai
WHERE
-- Remove inflight interceptions (ones which lack an ended_at value).
aibridge_interceptions.ended_at IS NOT NULL
ai.ended_at IS NOT NULL
-- Filter by time frame
AND CASE
WHEN @started_after::timestamptz != '0001-01-01 00:00:00+00'::timestamptz THEN aibridge_interceptions.started_at >= @started_after::timestamptz
WHEN @started_after::timestamptz != '0001-01-01 00:00:00+00'::timestamptz THEN ai.started_at >= @started_after::timestamptz
ELSE true
END
AND CASE
WHEN @started_before::timestamptz != '0001-01-01 00:00:00+00'::timestamptz THEN aibridge_interceptions.started_at <= @started_before::timestamptz
WHEN @started_before::timestamptz != '0001-01-01 00:00:00+00'::timestamptz THEN ai.started_at <= @started_before::timestamptz
ELSE true
END
-- Filter initiator_id
AND CASE
WHEN @initiator_id::uuid != '00000000-0000-0000-0000-000000000000'::uuid THEN aibridge_interceptions.initiator_id = @initiator_id::uuid
WHEN @initiator_id::uuid != '00000000-0000-0000-0000-000000000000'::uuid THEN ai.initiator_id = @initiator_id::uuid
ELSE true
END
-- Filter provider
AND CASE
WHEN @provider::text != '' THEN aibridge_interceptions.provider = @provider::text
WHEN @provider::text != '' THEN ai.provider = @provider::text
ELSE true
END
-- Filter model
AND CASE
WHEN @model::text != '' THEN aibridge_interceptions.model = @model::text
WHEN @model::text != '' THEN ai.model = @model::text
ELSE true
END
-- Filter client
AND CASE
WHEN @client::text != '' THEN COALESCE(aibridge_interceptions.client, 'Unknown') = @client::text
WHEN @client::text != '' THEN COALESCE(ai.client, 'Unknown') = @client::text
ELSE true
END
-- Filter session_id
AND CASE
WHEN @session_id::text != '' THEN aibridge_interceptions.session_id = @session_id::text
WHEN @session_id::text != '' THEN ai.session_id = @session_id::text
ELSE true
END
-- Authorize Filter clause will be injected below in ListAuthorizedAIBridgeSessions
-- @authorize_filter
),
session_tokens AS (
-- Aggregate token usage across all interceptions in each session.
-- Group by (session_id, initiator_id) to avoid merging sessions from
-- different users who happen to share the same client_session_id.
SELECT
fi.session_id,
fi.initiator_id,
COALESCE(SUM(tu.input_tokens), 0)::bigint AS input_tokens,
COALESCE(SUM(tu.output_tokens), 0)::bigint AS output_tokens
-- TODO: add extra token types once https://github.com/coder/aibridge/issues/150 lands.
FROM
filtered_interceptions fi
LEFT JOIN
aibridge_token_usages tu ON fi.id = tu.interception_id
GROUP BY
fi.session_id, fi.initiator_id
),
session_root AS (
-- Build one summary row per session. Group by (session_id, initiator_id)
-- to avoid merging sessions from different users who happen to share the
-- same client_session_id. The ARRAY_AGG with ORDER BY picks values from
-- the chronologically first interception for fields that should represent
-- the session as a whole (client, metadata). Threads are counted as
-- distinct root interception IDs: an interception with a NULL
-- thread_root_id is itself a thread root.
SELECT
fi.session_id,
fi.initiator_id,
(ARRAY_AGG(fi.client ORDER BY fi.started_at, fi.id))[1] AS client,
(ARRAY_AGG(fi.metadata ORDER BY fi.started_at, fi.id))[1] AS metadata,
ARRAY_AGG(DISTINCT fi.provider ORDER BY fi.provider) AS providers,
ARRAY_AGG(DISTINCT fi.model ORDER BY fi.model) AS models,
MIN(fi.started_at) AS started_at,
MAX(fi.ended_at) AS ended_at,
COUNT(DISTINCT COALESCE(fi.thread_root_id, fi.id)) AS threads,
-- Collect IDs for lateral prompt lookup.
ARRAY_AGG(fi.id) AS interception_ids
FROM
filtered_interceptions fi
GROUP BY
fi.session_id, fi.initiator_id
ai.session_id, ai.initiator_id
HAVING
-- Cursor pagination: uses a composite (started_at, session_id)
-- cursor to support keyset pagination. The less-than comparison
-- matches the DESC sort order so rows after the cursor come
-- later in results. The cursor value comes from cursor_pos to
-- guarantee single evaluation.
CASE
WHEN @after_session_id::text != '' THEN (
(MIN(ai.started_at), ai.session_id) < (
(SELECT started_at FROM cursor_pos),
@after_session_id::text
)
)
ELSE true
END
ORDER BY
MIN(ai.started_at) DESC,
ai.session_id DESC
LIMIT COALESCE(NULLIF(@limit_::integer, 0), 100)
OFFSET @offset_
)
SELECT
sr.session_id,
sp.session_id,
visible_users.id AS user_id,
visible_users.username AS user_username,
visible_users.name AS user_name,
@@ -551,45 +547,48 @@ SELECT
sr.models::text[] AS models,
COALESCE(sr.client, '')::varchar(64) AS client,
sr.metadata::jsonb AS metadata,
sr.started_at::timestamptz AS started_at,
sr.ended_at::timestamptz AS ended_at,
sr.threads,
sp.started_at::timestamptz AS started_at,
sp.ended_at::timestamptz AS ended_at,
sp.threads,
COALESCE(st.input_tokens, 0)::bigint AS input_tokens,
COALESCE(st.output_tokens, 0)::bigint AS output_tokens,
COALESCE(slp.prompt, '') AS last_prompt
FROM
session_root sr
session_page sp
JOIN
visible_users ON visible_users.id = sr.initiator_id
LEFT JOIN
session_tokens st ON st.session_id = sr.session_id AND st.initiator_id = sr.initiator_id
visible_users ON visible_users.id = sp.initiator_id
LEFT JOIN LATERAL (
-- Lateral join to efficiently fetch only the most recent user prompt
-- across all interceptions in the session, avoiding a full aggregation.
SELECT
(ARRAY_AGG(ai.client ORDER BY ai.started_at, ai.id))[1] AS client,
(ARRAY_AGG(ai.metadata ORDER BY ai.started_at, ai.id))[1] AS metadata,
ARRAY_AGG(DISTINCT ai.provider ORDER BY ai.provider) AS providers,
ARRAY_AGG(DISTINCT ai.model ORDER BY ai.model) AS models,
ARRAY_AGG(ai.id) AS interception_ids
FROM aibridge_interceptions ai
WHERE ai.session_id = sp.session_id
AND ai.initiator_id = sp.initiator_id
AND ai.ended_at IS NOT NULL
) sr ON true
LEFT JOIN LATERAL (
-- Aggregate tokens only for this session's interceptions.
SELECT
COALESCE(SUM(tu.input_tokens), 0)::bigint AS input_tokens,
COALESCE(SUM(tu.output_tokens), 0)::bigint AS output_tokens
FROM aibridge_token_usages tu
WHERE tu.interception_id = ANY(sr.interception_ids)
) st ON true
LEFT JOIN LATERAL (
-- Fetch only the most recent user prompt across all interceptions
-- in the session.
SELECT up.prompt
FROM aibridge_user_prompts up
WHERE up.interception_id = ANY(sr.interception_ids)
ORDER BY up.created_at DESC, up.id DESC
LIMIT 1
) slp ON true
WHERE
-- Cursor pagination: uses a composite (started_at, session_id) cursor
-- to support keyset pagination. The less-than comparison matches the
-- DESC sort order so that rows after the cursor come later in results.
CASE
WHEN @after_session_id::text != '' THEN (
(sr.started_at, sr.session_id) < (
(SELECT started_at FROM session_root WHERE session_id = @after_session_id),
@after_session_id::text
)
)
ELSE true
END
ORDER BY
sr.started_at DESC,
sr.session_id DESC
LIMIT COALESCE(NULLIF(@limit_::integer, 0), 100)
OFFSET @offset_
sp.started_at DESC,
sp.session_id DESC
;
-- name: ListAIBridgeSessionThreads :many