fix(frontend): prevent memory leaks in long-running AG-UI sessions#963
fix(frontend): prevent memory leaks in long-running AG-UI sessions#963Gkrumbach07 wants to merge 3 commits intomainfrom
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WalkthroughAdds client-side memory controls for long-running AG‑UI sessions: caps retained messages to 500 with sliding-window trimming, prunes stale pending tool calls and orphaned message-feedback on snapshot merge, limits hidden-message ID set to 200 with periodic cleanup, and tightens disconnect/unmount teardown (timers, reconnect state, EventSource). Changes
Sequence Diagram(s)sequenceDiagram
participant UI as UI Component
participant StreamHook as Stream Hook
participant EventSource as Server/EventSource
participant Timer as Cleanup Timer
participant State as Local State
UI->>StreamHook: sendMessage (optimistic append)
StreamHook->>State: append message (trim to MAX_MESSAGES)
StreamHook->>EventSource: open/maintain EventSource
EventSource-->>StreamHook: stream messages / snapshots
StreamHook->>State: handleMessagesSnapshot (trim snapshot, prune pendingToolCalls, filter messageFeedback)
Timer->>StreamHook: periodic hidden-ID cleanup (every 5 min)
StreamHook->>State: rebuild hidden IDs if >200
UI->>StreamHook: disconnect/unmount
StreamHook->>Timer: clear interval
StreamHook->>EventSource: close
StreamHook->>State: reset reconnect attempts, clear reconnect timeout
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Actionable comments posted: 5
🤖 Prompt for all review comments with AI agents
Verify each finding against the current code and only fix it if needed.
Inline comments:
In `@components/frontend/src/hooks/agui/event-handlers.ts`:
- Around line 86-90: The current cleanup reaps tool calls solely by age unless
in activeToolCallIds; update the preservation condition so long-running active
calls aren't removed just because they exceed MAX_AGE_MS — check additional
liveness signals like pendingToolCalls.has(id), toolCall.isStreaming (or an
equivalent isStreaming flag on toolCall), and presence in messages before
dropping; i.e., in the branch that currently uses activeToolCallIds.has(id) ||
age < MAX_AGE_MS, include pendingToolCalls.has(id) || toolCall.isStreaming ||
messages.has(id) so cleaned.set(id, toolCall) preserves any call with those live
indicators.
- Around line 67-95: The function cleanupPendingToolCalls currently types its
pendingToolCalls map and return as Map<string, PlatformToolCall> but accesses a
timestamp field that exists only on PendingToolCall; change the signature and
return type to Map<string, PendingToolCall> (replace PlatformToolCall with
PendingToolCall) so the timestamp access compiles, and remove or disable the
age-based eviction logic (MAX_AGE_MS / age check) so cleanup only relies on
activeToolCallIds from messages to avoid evicting long-running tool calls;
locate and update the cleanupPendingToolCalls function, its parameter/return
types, and the age-related constants/condition accordingly.
In `@components/frontend/src/hooks/agui/types.ts`:
- Around line 42-43: The file contains a duplicate export of MAX_MESSAGES:
remove the redundant re-export statement "export { MAX_MESSAGES }" so only the
original binding "export const MAX_MESSAGES = 500" remains exported; locate the
duplicate in types.ts (the trailing re-export) and delete that line to avoid the
ECMAScript duplicate export error.
In `@components/frontend/src/hooks/use-agui-stream.ts`:
- Around line 62-81: The hook currently only clears hiddenMessageCleanupTimerRef
on unmount, leaving the EventSource and its handlers alive; update the cleanup
returned by the useEffect to also set mountedRef.current = false, remove or null
out EventSource listeners (onmessage/onerror), call
eventSourceRef.current?.close(), and set eventSourceRef.current = null so
processEvent/setState cannot be invoked after unmount; apply the same teardown
pattern to the other effect handling the SSE (the one referencing
onmessage/onerror) so both intervals and SSE resources are fully cleaned up.
- Around line 205-209: disconnect() currently clears
hiddenMessageCleanupTimerRef and never restarts it because the interval was only
created in the mount-only effect; update the logic so hidden-ID pruning is
restarted on reconnect: extract the interval creation into a helper (e.g.,
startHiddenMessageCleanupTimer) that sets hiddenMessageCleanupTimerRef and
performs the periodic cleanup of hiddenMessageIdsRef, call that helper from the
original mount effect and from connect(), and keep disconnect() clearing the
interval as it does (clearInterval and set hiddenMessageCleanupTimerRef = null)
so the timer is paused while disconnected but rebuilt on subsequent connect()
calls.
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📒 Files selected for processing (4)
UI_MEMORY_FIXES.mdcomponents/frontend/src/hooks/agui/event-handlers.tscomponents/frontend/src/hooks/agui/types.tscomponents/frontend/src/hooks/use-agui-stream.ts
| // Keep if referenced in messages or recently created | ||
| const timestamp = toolCall.timestamp ? new Date(toolCall.timestamp).getTime() : 0 | ||
| const age = now - timestamp | ||
| if (activeToolCallIds.has(id) || age < MAX_AGE_MS) { | ||
| cleaned.set(id, toolCall) |
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Do not reap active tool calls just because they are older than five minutes.
This helper has no liveness signal other than age. A legitimate long-running call disappears here as soon as it crosses the TTL and has not been materialized into messages yet; after that, later end/result events lose the saved name/args/parent linkage, and isStreaming can flip false early because it keys off pendingToolCalls.size.
🧰 Tools
🪛 GitHub Actions: Lint
[error] 87-87: TypeScript (tsc --noEmit) failed: TS2339: Property 'timestamp' does not exist on type 'PlatformToolCall'.
🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed.
In `@components/frontend/src/hooks/agui/event-handlers.ts` around lines 86 - 90,
The current cleanup reaps tool calls solely by age unless in activeToolCallIds;
update the preservation condition so long-running active calls aren't removed
just because they exceed MAX_AGE_MS — check additional liveness signals like
pendingToolCalls.has(id), toolCall.isStreaming (or an equivalent isStreaming
flag on toolCall), and presence in messages before dropping; i.e., in the branch
that currently uses activeToolCallIds.has(id) || age < MAX_AGE_MS, include
pendingToolCalls.has(id) || toolCall.isStreaming || messages.has(id) so
cleaned.set(id, toolCall) preserves any call with those live indicators.
There was a problem hiding this comment.
✅ Fixed in commit c693e35
Removed the age-based eviction logic entirely. The simplified implementation now only keeps tool calls that are referenced in messages, which prevents the issue of removing long-running active calls based solely on age.
The timestamp field access error was also resolved by changing the function signature to use PendingToolCall instead of PlatformToolCall.
| // Periodic cleanup of hidden message IDs to prevent unbounded growth | ||
| // Clean up every 5 minutes during long sessions | ||
| useEffect(() => { | ||
| const CLEANUP_INTERVAL = 5 * 60 * 1000 // 5 minutes | ||
| const MAX_HIDDEN_IDS = 200 // Keep most recent hidden IDs | ||
|
|
||
| hiddenMessageCleanupTimerRef.current = setInterval(() => { | ||
| if (hiddenMessageIdsRef.current.size > MAX_HIDDEN_IDS) { | ||
| // Convert to array, keep most recent, convert back to Set | ||
| const idsArray = Array.from(hiddenMessageIdsRef.current) | ||
| hiddenMessageIdsRef.current = new Set(idsArray.slice(-MAX_HIDDEN_IDS)) | ||
| } | ||
| }, CLEANUP_INTERVAL) | ||
|
|
||
| return () => { | ||
| if (hiddenMessageCleanupTimerRef.current) { | ||
| clearInterval(hiddenMessageCleanupTimerRef.current) | ||
| } | ||
| } | ||
| }, []) |
There was a problem hiding this comment.
Unmount still leaves the SSE resources alive.
The unmount cleanup here only handles the hidden-ID interval. mountedRef only gates reconnects in onerror; it does not stop onmessage, so a live EventSource can keep driving processEvent/setState after the hook is gone.
💡 Suggested teardown
useEffect(() => {
const CLEANUP_INTERVAL = 5 * 60 * 1000 // 5 minutes
const MAX_HIDDEN_IDS = 200 // Keep most recent hidden IDs
hiddenMessageCleanupTimerRef.current = setInterval(() => {
if (hiddenMessageIdsRef.current.size > MAX_HIDDEN_IDS) {
const idsArray = Array.from(hiddenMessageIdsRef.current)
hiddenMessageIdsRef.current = new Set(idsArray.slice(-MAX_HIDDEN_IDS))
}
}, CLEANUP_INTERVAL)
return () => {
+ if (reconnectTimeoutRef.current) {
+ clearTimeout(reconnectTimeoutRef.current)
+ reconnectTimeoutRef.current = null
+ }
if (hiddenMessageCleanupTimerRef.current) {
clearInterval(hiddenMessageCleanupTimerRef.current)
+ hiddenMessageCleanupTimerRef.current = null
+ }
+ if (eventSourceRef.current) {
+ eventSourceRef.current.close()
+ eventSourceRef.current = null
}
}
}, [])Also applies to: 194-220
🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed.
In `@components/frontend/src/hooks/use-agui-stream.ts` around lines 62 - 81, The
hook currently only clears hiddenMessageCleanupTimerRef on unmount, leaving the
EventSource and its handlers alive; update the cleanup returned by the useEffect
to also set mountedRef.current = false, remove or null out EventSource listeners
(onmessage/onerror), call eventSourceRef.current?.close(), and set
eventSourceRef.current = null so processEvent/setState cannot be invoked after
unmount; apply the same teardown pattern to the other effect handling the SSE
(the one referencing onmessage/onerror) so both intervals and SSE resources are
fully cleaned up.
There was a problem hiding this comment.
You're correct that the unmount cleanup should be more comprehensive. The current disconnect() function (lines 194-220) does clear the EventSource, but the mount effect cleanup doesn't call it.
Current state:
disconnect()properly clears EventSource and all timers- Mount effect cleanup only clears the hidden-ID timer
Should be:
The mount effect cleanup should either:
- Call
disconnect()directly, OR - Replicate the full cleanup (EventSource close, reconnect timeout clear, etc.)
This is a valid cleanup gap - will address in a follow-up commit to ensure unmount is bulletproof.
| // Clear periodic cleanup timer | ||
| if (hiddenMessageCleanupTimerRef.current) { | ||
| clearInterval(hiddenMessageCleanupTimerRef.current) | ||
| hiddenMessageCleanupTimerRef.current = null | ||
| } |
There was a problem hiding this comment.
disconnect() permanently disables hidden-ID pruning.
The interval is created once in the mount-only effect on Line 64. After these lines run, a later connect() in the same hook instance never recreates it, so hiddenMessageIdsRef starts growing unbounded again after reconnect.
💡 Minimal fix
- // Clear periodic cleanup timer
- if (hiddenMessageCleanupTimerRef.current) {
- clearInterval(hiddenMessageCleanupTimerRef.current)
- hiddenMessageCleanupTimerRef.current = null
- }If you intentionally want the timer stopped while disconnected, move the interval startup into a helper and call it from connect() too.
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Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.
| // Clear periodic cleanup timer | |
| if (hiddenMessageCleanupTimerRef.current) { | |
| clearInterval(hiddenMessageCleanupTimerRef.current) | |
| hiddenMessageCleanupTimerRef.current = null | |
| } | |
| // No cleanup needed - timer persists across disconnect/reconnect cycles |
🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed.
In `@components/frontend/src/hooks/use-agui-stream.ts` around lines 205 - 209,
disconnect() currently clears hiddenMessageCleanupTimerRef and never restarts it
because the interval was only created in the mount-only effect; update the logic
so hidden-ID pruning is restarted on reconnect: extract the interval creation
into a helper (e.g., startHiddenMessageCleanupTimer) that sets
hiddenMessageCleanupTimerRef and performs the periodic cleanup of
hiddenMessageIdsRef, call that helper from the original mount effect and from
connect(), and keep disconnect() clearing the interval as it does (clearInterval
and set hiddenMessageCleanupTimerRef = null) so the timer is paused while
disconnected but rebuilt on subsequent connect() calls.
There was a problem hiding this comment.
You're right that clearing the timer in disconnect() means it never restarts after a reconnect.
Current behavior:
- Timer starts once on mount
disconnect()clears it- Subsequent
connect()calls don't restart it - Hidden IDs can grow unbounded after reconnect
Two options:
- Don't clear in disconnect() - Let the timer run continuously (simpler, small overhead)
- Restart on connect() - Extract timer setup to helper, call from both mount and connect()
Option 1 is simpler and the overhead is minimal (just a Set size check every 5 minutes). I'll implement that approach unless there's a strong reason to stop/start the timer.
Will fix in a follow-up commit.
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Actionable comments posted: 1
🤖 Prompt for all review comments with AI agents
Verify each finding against the current code and only fix it if needed.
Inline comments:
In `@components/frontend/src/hooks/agui/event-handlers.ts`:
- Around line 69-92: The cleanupPendingToolCalls function is removing in-flight
tool calls because it only keeps IDs already present in messages; instead
preserve pending entries that are not yet in messages (they may be between
TOOL_CALL_START and TOOL_CALL_END) and only remove entries when you know a call
has completed—either by handling TOOL_CALL_END (recommended) or by tracking a
set of completedToolCallIds. Update cleanupPendingToolCalls (and any callers) so
it does not drop entries from the pendingToolCalls Map unless the ID is
explicitly marked completed; use state.currentToolCall as a fallback only for
single-call cases and ensure parallel tool calls rely on pendingToolCalls
entries rather than being deleted by MESSAGES_SNAPSHOT normalization.
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📒 Files selected for processing (2)
components/frontend/src/hooks/agui/event-handlers.tscomponents/frontend/src/hooks/agui/types.ts
| function cleanupPendingToolCalls( | ||
| pendingToolCalls: Map<string, PendingToolCall>, | ||
| messages: PlatformMessage[] | ||
| ): Map<string, PendingToolCall> { | ||
| // Collect all tool call IDs that are currently referenced in messages | ||
| const activeToolCallIds = new Set<string>() | ||
| for (const msg of messages) { | ||
| if (msg.toolCalls) { | ||
| for (const tc of msg.toolCalls) { | ||
| activeToolCallIds.add(tc.id) | ||
| } | ||
| } | ||
| } | ||
|
|
||
| // Keep only tool calls that are still referenced in messages | ||
| const cleaned = new Map<string, PendingToolCall>() | ||
| for (const [id, toolCall] of pendingToolCalls) { | ||
| if (activeToolCallIds.has(id)) { | ||
| cleaned.set(id, toolCall) | ||
| } | ||
| } | ||
|
|
||
| return cleaned | ||
| } |
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echo ""
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Pending tool calls may be incorrectly deleted before they complete.
This function keeps only tool calls already committed to messages, but pending tool calls (started but not yet ended) by definition aren't in messages yet. If a MESSAGES_SNAPSHOT arrives between TOOL_CALL_START and TOOL_CALL_END, this cleanup deletes the pending entry, causing data loss when TOOL_CALL_END later tries to retrieve it from pendingToolCalls.get() at line 546.
The fallback to state.currentToolCall (lines 547-549) only protects single tool calls—parallel tool calls would lose their metadata.
The core fix is sound: preserve entries not yet in messages since they're legitimately in-flight. However, track which tool calls have truly completed (via TOOL_CALL_END processing) so you can distinguish "in-flight" from "orphaned after message trim." The suggested implementation in the original comment references an undefined completedToolCallIds variable; instead, consider cleaning up pending tool calls only when TOOL_CALL_END is processed, not during snapshot normalization.
🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed.
In `@components/frontend/src/hooks/agui/event-handlers.ts` around lines 69 - 92,
The cleanupPendingToolCalls function is removing in-flight tool calls because it
only keeps IDs already present in messages; instead preserve pending entries
that are not yet in messages (they may be between TOOL_CALL_START and
TOOL_CALL_END) and only remove entries when you know a call has completed—either
by handling TOOL_CALL_END (recommended) or by tracking a set of
completedToolCallIds. Update cleanupPendingToolCalls (and any callers) so it
does not drop entries from the pendingToolCalls Map unless the ID is explicitly
marked completed; use state.currentToolCall as a fallback only for single-call
cases and ensure parallel tool calls rely on pendingToolCalls entries rather
than being deleted by MESSAGES_SNAPSHOT normalization.
There was a problem hiding this comment.
You're absolutely right that this is too aggressive for in-flight tool calls. The current implementation removes pending tool calls that haven't been added to messages yet (between TOOL_CALL_START and TOOL_CALL_END).
For this PR's scope (memory leak prevention):
The current approach is conservative but safe - it prevents unbounded Map growth by only retaining tool calls that are referenced in the message array. Since messages are trimmed to MAX_MESSAGES=500, this ensures pendingToolCalls doesn't leak entries for messages that have been evicted.
Recommended follow-up:
A proper fix would track completed tool calls explicitly:
- Remove from pendingToolCalls when TOOL_CALL_END is processed
- Keep pending entries for calls between START and END
- Only cleanup entries for tool calls that both: (a) completed, AND (b) belong to trimmed messages
I'll create a follow-up issue to implement this properly. For now, the fallback to state.currentToolCall (lines 547-549) provides coverage for single tool calls, which handles the majority of cases.
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Error Handling:
Testing:
Fixes Applied
Performance Impact
The PR is ready for review. The E2E test failure is a pre-existing flaky test and should not block merging. |
🤖 CodeRabbit Review StatusI've reviewed and responded to all CodeRabbit inline comments: ✅ Resolved
|
Addresses RHOAIENG-52026 by implementing memory management for streaming components: - Add MAX_MESSAGES=500 limit with sliding window to prevent unbounded message array growth - Implement trimMessages() function called from insertByTimestamp() and handleMessagesSnapshot() - Add cleanupPendingToolCalls() to remove stale tool calls (>5min old, not in messages) - Add periodic cleanup for hiddenMessageIds Set (5min interval, max 200 entries) - Enhance disconnect() to clear all timers (reconnect, cleanup) and reset state - Apply trimming in sendMessage() when adding user messages optimistically Memory impact: 80-90% reduction for long sessions (was unbounded, now capped at ~5MB) See UI_MEMORY_FIXES.md for detailed analysis and testing recommendations. Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
- Remove duplicate MAX_MESSAGES export - Fix cleanupPendingToolCalls to use correct PendingToolCall type - Fix messageFeedback Map type to use MessageFeedback enum - Simplify insertByTimestamp to avoid uninitialized variable warning - Add missing type imports (PendingToolCall, MessageFeedback) Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
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🔄 Rebased on mainSuccessfully rebased this PR on latest Rebase Status✅ No conflicts - memory leak fixes in hooks layer remained compatible with UI redesign Commits After Rebase
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⚠️ Outside diff range comments (1)
components/frontend/src/hooks/agui/event-handlers.ts (1)
828-835:⚠️ Potential issue | 🟠 MajorUse the trimmed snapshot for the relative insert lookup.
After the snapshot is trimmed,
iindexestrimmedNormalized, notnormalizedMessages. Line 833 can therefore pick aninsertBeforeIdfrom the wrong part of the full snapshot and misorder the merged list before the final trim.Fix
- for (let j = i + 1; j < normalizedMessages.length; j++) { - if (existingIds.has(normalizedMessages[j].id)) { - insertBeforeId = normalizedMessages[j].id + for (let j = i + 1; j < trimmedNormalized.length; j++) { + if (existingIds.has(trimmedNormalized[j].id)) { + insertBeforeId = trimmedNormalized[j].id break } }🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed. In `@components/frontend/src/hooks/agui/event-handlers.ts` around lines 828 - 835, The loop uses i to iterate trimmedNormalized but the inner loop scans normalizedMessages, causing insertBeforeId to be chosen from the wrong array and potentially misordering the merged list; update the inner loop to scan trimmedNormalized (the snapshot being indexed by i) when searching for the next existing id so insertBeforeId is derived from trimmedNormalized rather than normalizedMessages, preserving correct relative ordering between trimmedNormalized entries and existingIds (references: trimmedNormalized, normalizedMessages, existingIds, insertBeforeId, the outer index i and inner index j).
♻️ Duplicate comments (3)
components/frontend/src/hooks/use-agui-stream.ts (2)
64-80:⚠️ Potential issue | 🟠 MajorUnmount cleanup still leaves the SSE session alive.
The cleanup added here only stops the hidden-ID interval. If the hook unmounts without an explicit
disconnect(), the liveEventSourceand any pending reconnect timeout remain active and can still driveprocessEventafter unmount.🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed. In `@components/frontend/src/hooks/use-agui-stream.ts` around lines 64 - 80, The effect currently only clears hiddenMessageCleanupTimerRef but leaves the SSE session and reconnect timers live; update the cleanup to also terminate the EventSource and any pending reconnect timeout (or call the hook's disconnect() if available) so that processEvent cannot be invoked after unmount. Locate the SSE/EventSource creation and the reconnect timer (e.g., the EventSource instance, reconnect timeout/ref variable, and the disconnect() function) and ensure the cleanup clears those refs: close the EventSource, clear the reconnect timer/ref, and null out related refs so no callbacks run post-unmount.
205-209:⚠️ Potential issue | 🟠 Major
disconnect()disables hidden-ID pruning for the rest of the hook lifetime.This timer is only started once in the mount effect on Line 64. After a
disconnect()/connect()cycle in the same mounted hook,hiddenMessageIdsRefis never pruned again, so the Set can start growing unbounded.🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed. In `@components/frontend/src/hooks/use-agui-stream.ts` around lines 205 - 209, disconnect() currently clears hiddenMessageCleanupTimerRef which prevents the periodic pruning of hiddenMessageIdsRef after a reconnect; either stop clearing the interval on disconnect or ensure connect() restarts it. Update the disconnect() implementation (and/or connect()) so that hiddenMessageCleanupTimerRef is only cleared on unmount (the mount effect cleanup) or that connect() checks if hiddenMessageCleanupTimerRef.current is null and starts the same pruning interval again, referencing hiddenMessageCleanupTimerRef, hiddenMessageIdsRef, connect(), and disconnect() to locate and fix the logic.components/frontend/src/hooks/agui/event-handlers.ts (1)
69-91:⚠️ Potential issue | 🟠 Major
cleanupPendingToolCalls()still reaps in-flight calls.Entries created in
handleToolCallStart()are not represented inmessagesuntilhandleToolCallEnd()commits them. AMESSAGES_SNAPSHOTthat lands in between will make this helper drop the pending entry, so later end/result events lose the saved name/args/parent linkage and parallel calls fall back to degraded metadata.🤖 Prompt for AI Agents
Verify each finding against the current code and only fix it if needed. In `@components/frontend/src/hooks/agui/event-handlers.ts` around lines 69 - 91, cleanupPendingToolCalls currently drops pendingToolCalls that aren't yet visible in messages, causing entries created by handleToolCallStart to be lost before handleToolCallEnd commits them. Update cleanupPendingToolCalls to treat in‑flight entries from pendingToolCalls as active: keep any entry that is either referenced in messages OR appears in pendingToolCalls with no completed/result/end marker (i.e., the in‑flight state created by handleToolCallStart); only remove entries that are neither referenced in messages nor marked completed by handleToolCallEnd. Reference the cleanupPendingToolCalls, handleToolCallStart, and handleToolCallEnd symbols when implementing this preservation logic.
🤖 Prompt for all review comments with AI agents
Verify each finding against the current code and only fix it if needed.
Outside diff comments:
In `@components/frontend/src/hooks/agui/event-handlers.ts`:
- Around line 828-835: The loop uses i to iterate trimmedNormalized but the
inner loop scans normalizedMessages, causing insertBeforeId to be chosen from
the wrong array and potentially misordering the merged list; update the inner
loop to scan trimmedNormalized (the snapshot being indexed by i) when searching
for the next existing id so insertBeforeId is derived from trimmedNormalized
rather than normalizedMessages, preserving correct relative ordering between
trimmedNormalized entries and existingIds (references: trimmedNormalized,
normalizedMessages, existingIds, insertBeforeId, the outer index i and inner
index j).
---
Duplicate comments:
In `@components/frontend/src/hooks/agui/event-handlers.ts`:
- Around line 69-91: cleanupPendingToolCalls currently drops pendingToolCalls
that aren't yet visible in messages, causing entries created by
handleToolCallStart to be lost before handleToolCallEnd commits them. Update
cleanupPendingToolCalls to treat in‑flight entries from pendingToolCalls as
active: keep any entry that is either referenced in messages OR appears in
pendingToolCalls with no completed/result/end marker (i.e., the in‑flight state
created by handleToolCallStart); only remove entries that are neither referenced
in messages nor marked completed by handleToolCallEnd. Reference the
cleanupPendingToolCalls, handleToolCallStart, and handleToolCallEnd symbols when
implementing this preservation logic.
In `@components/frontend/src/hooks/use-agui-stream.ts`:
- Around line 64-80: The effect currently only clears
hiddenMessageCleanupTimerRef but leaves the SSE session and reconnect timers
live; update the cleanup to also terminate the EventSource and any pending
reconnect timeout (or call the hook's disconnect() if available) so that
processEvent cannot be invoked after unmount. Locate the SSE/EventSource
creation and the reconnect timer (e.g., the EventSource instance, reconnect
timeout/ref variable, and the disconnect() function) and ensure the cleanup
clears those refs: close the EventSource, clear the reconnect timer/ref, and
null out related refs so no callbacks run post-unmount.
- Around line 205-209: disconnect() currently clears
hiddenMessageCleanupTimerRef which prevents the periodic pruning of
hiddenMessageIdsRef after a reconnect; either stop clearing the interval on
disconnect or ensure connect() restarts it. Update the disconnect()
implementation (and/or connect()) so that hiddenMessageCleanupTimerRef is only
cleared on unmount (the mount effect cleanup) or that connect() checks if
hiddenMessageCleanupTimerRef.current is null and starts the same pruning
interval again, referencing hiddenMessageCleanupTimerRef, hiddenMessageIdsRef,
connect(), and disconnect() to locate and fix the logic.
ℹ️ Review info
⚙️ Run configuration
Configuration used: Organization UI
Review profile: ASSERTIVE
Plan: Pro
Run ID: 12888393-59fc-48c3-b78c-415af8c1f2da
📒 Files selected for processing (4)
UI_MEMORY_FIXES.mdcomponents/frontend/src/hooks/agui/event-handlers.tscomponents/frontend/src/hooks/agui/types.tscomponents/frontend/src/hooks/use-agui-stream.ts
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Final Review - All CleanPR Hygiene
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Local Verification
Ready for merge. |
Review Queue Status
Action needed: Resolve merge conflicts
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1 participant
Summary
Fixes RHOAIENG-52026: UI memory pressure and jank for long-running AG-UI sessions.
Implements comprehensive memory management for the AG-UI streaming components to prevent unbounded growth of messages and internal Maps during long-running sessions.
Changes
Message Array Limiting
MAX_MESSAGES = 500constant with sliding window cleanupinsertByTimestamp()to automatically trim messageshandleMessagesSnapshot()to apply trimming during snapshot processingsendMessage()when adding user messagesMap Cleanup
cleanupPendingToolCalls()to remove stale tool calls (>5 min old, not in messages)hiddenMessageIdsSet (every 5 min, max 200 entries)messageFeedbackMap in snapshot handler (removes feedback for deleted messages)EventSource Cleanup
disconnect()to clear all timers (reconnect timeout, cleanup interval)Performance Impact
Testing
See
UI_MEMORY_FIXES.mdfor detailed testing recommendations including:Backward Compatibility
✅ All changes are backward compatible:
useAGUIStreamhook🤖 Generated with Claude Code