diff --git a/open-sse/handlers/chatCore/nonStreamingHandler.js b/open-sse/handlers/chatCore/nonStreamingHandler.js
index d1610058..0053e9b1 100644
--- a/open-sse/handlers/chatCore/nonStreamingHandler.js
+++ b/open-sse/handlers/chatCore/nonStreamingHandler.js
@@ -167,7 +167,13 @@ export async function handleNonStreamingResponse({ providerResponse, provider, m
   }
 
   reqLogger.logProviderResponse(providerResponse.status, providerResponse.statusText, providerResponse.headers, responseBody);
-  if (onRequestSuccess) await onRequestSuccess();
+  if (onRequestSuccess) {
+    Promise.resolve()
+      .then(onRequestSuccess)
+      .catch(err => {
+        console.error("[ChatCore] onRequestSuccess failed:", err?.message || err);
+      });
+  }
 
   // Decloak tool_use names once on raw Claude body, before any translation (INPUT side)
   responseBody = decloakToolNames(responseBody, toolNameMap);
diff --git a/open-sse/handlers/chatCore/streamingHandler.js b/open-sse/handlers/chatCore/streamingHandler.js
index aa907cd5..d91bb3a2 100644
--- a/open-sse/handlers/chatCore/streamingHandler.js
+++ b/open-sse/handlers/chatCore/streamingHandler.js
@@ -44,7 +44,13 @@ function buildTransformStream({ provider, sourceFormat, targetFormat, userAgent,
  * Handle streaming response — pipe provider SSE through transform stream to client.
  */
 export function handleStreamingResponse({ providerResponse, provider, model, sourceFormat, targetFormat, userAgent, body, stream, translatedBody, finalBody, requestStartTime, connectionId, apiKey, clientRawRequest, onRequestSuccess, reqLogger, toolNameMap, streamController, onStreamComplete }) {
-  if (onRequestSuccess) onRequestSuccess();
+  if (onRequestSuccess) {
+    Promise.resolve()
+      .then(onRequestSuccess)
+      .catch(err => {
+        console.error("[ChatCore] onRequestSuccess failed:", err?.message || err);
+      });
+  }
 
   const transformStream = buildTransformStream({ provider, sourceFormat, targetFormat, userAgent, reqLogger, toolNameMap, model, connectionId, body, onStreamComplete, apiKey });
 
diff --git a/src/app/(dashboard)/dashboard/console-log/ConsoleLogClient.js b/src/app/(dashboard)/dashboard/console-log/ConsoleLogClient.js
index 6373015d..01a8a757 100644
--- a/src/app/(dashboard)/dashboard/console-log/ConsoleLogClient.js
+++ b/src/app/(dashboard)/dashboard/console-log/ConsoleLogClient.js
@@ -47,6 +47,11 @@ export default function ConsoleLogClient() {
           const next = [...prev, msg.line];
           return next.length > CONSOLE_LOG_CONFIG.maxLines ? next.slice(-CONSOLE_LOG_CONFIG.maxLines) : next;
         });
+      } else if (msg.type === "lines") {
+        setLogs((prev) => {
+          const next = [...prev, ...msg.lines];
+          return next.length > CONSOLE_LOG_CONFIG.maxLines ? next.slice(-CONSOLE_LOG_CONFIG.maxLines) : next;
+        });
       } else if (msg.type === "clear") {
         setLogs([]);
       }
diff --git a/src/app/api/translator/console-logs/stream/route.js b/src/app/api/translator/console-logs/stream/route.js
index e90f11f7..5eb3ae37 100644
--- a/src/app/api/translator/console-logs/stream/route.js
+++ b/src/app/api/translator/console-logs/stream/route.js
@@ -7,13 +7,14 @@ initConsoleLogCapture();
 export async function GET(request) {
   const encoder = new TextEncoder();
   const emitter = getConsoleEmitter();
-  const state = { closed: false, send: null, sendClear: null, keepalive: null };
+  const state = { closed: false, send: null, sendLines: null, sendClear: null, keepalive: null };
 
   // Idempotent: safe to call from request.signal abort, cancel(), or enqueue failure.
   const cleanup = () => {
     if (state.closed) return;
     state.closed = true;
     if (state.send) emitter.off("line", state.send);
+    if (state.sendLines) emitter.off("lines", state.sendLines);
     if (state.sendClear) emitter.off("clear", state.sendClear);
     if (state.keepalive) clearInterval(state.keepalive);
   };
@@ -40,6 +41,15 @@ export async function GET(request) {
         }
       };
 
+      state.sendLines = (lines) => {
+        if (state.closed || !Array.isArray(lines) || lines.length === 0) return;
+        try {
+          controller.enqueue(encoder.encode(`data: ${JSON.stringify({ type: "lines", lines })}\n\n`));
+        } catch {
+          cleanup();
+        }
+      };
+
       // Notify client when cleared
       state.sendClear = () => {
         if (state.closed) return;
@@ -51,6 +61,7 @@ export async function GET(request) {
       };
 
       emitter.on("line", state.send);
+      emitter.on("lines", state.sendLines);
       emitter.on("clear", state.sendClear);
 
       // Keepalive ping every 25s
diff --git a/src/lib/consoleLogBuffer.js b/src/lib/consoleLogBuffer.js
index afff411f..9ace30fb 100644
--- a/src/lib/consoleLogBuffer.js
+++ b/src/lib/consoleLogBuffer.js
@@ -21,6 +21,26 @@ if (!state.emitter) {
   state.emitter.setMaxListeners(50);
 }
 
+if (!state.pendingLines) state.pendingLines = [];
+if (!state.flushTimer) state.flushTimer = null;
+
+const FLUSH_INTERVAL_MS = 100;
+const MAX_BATCH_LINES = 50;
+
+function flushPendingLines() {
+  state.flushTimer = null;
+  if (!state.pendingLines.length) return;
+
+  const lines = state.pendingLines.splice(0, state.pendingLines.length);
+  state.emitter.emit("lines", lines);
+}
+
+function scheduleFlush() {
+  if (state.flushTimer) return;
+  state.flushTimer = setTimeout(flushPendingLines, FLUSH_INTERVAL_MS);
+  state.flushTimer?.unref?.();
+}
+
 function toLogLine(level, args) {
   return args.map(formatArg).join(" ");
 }
@@ -48,7 +68,16 @@ function appendLine(line) {
   if (state.logs.length > maxLines) {
     state.logs = state.logs.slice(-maxLines);
   }
-  state.emitter.emit("line", line);
+  state.pendingLines.push(line);
+  if (state.pendingLines.length >= MAX_BATCH_LINES) {
+    if (state.flushTimer) {
+      clearTimeout(state.flushTimer);
+      state.flushTimer = null;
+    }
+    flushPendingLines();
+  } else {
+    scheduleFlush();
+  }
 }
 
 export function initConsoleLogCapture() {
diff --git a/src/lib/db/repos/usageRepo.js b/src/lib/db/repos/usageRepo.js
index 8bd632ad..c6b6cb56 100644
--- a/src/lib/db/repos/usageRepo.js
+++ b/src/lib/db/repos/usageRepo.js
@@ -18,15 +18,27 @@ if (!global._statsEmitter) {
 if (!global._pendingTimers) global._pendingTimers = {};
 if (!global._recentRing) global._recentRing = { items: [], initialized: false };
 if (!global._connectionMapCache) global._connectionMapCache = { map: {}, ts: 0 };
+if (!global._statsEmitTimers) global._statsEmitTimers = { pending: null, update: null };
 
 const pendingRequests = global._pendingRequests;
 const lastErrorProvider = global._lastErrorProvider;
 const pendingTimers = global._pendingTimers;
 const recentRing = global._recentRing;
 const connCache = global._connectionMapCache;
+const statsEmitTimers = global._statsEmitTimers;
 
 export const statsEmitter = global._statsEmitter;
 
+function scheduleStatsEvent(event, delayMs = 150) {
+  const key = event === "update" ? "update" : "pending";
+  if (statsEmitTimers[key]) return;
+  statsEmitTimers[key] = setTimeout(() => {
+    statsEmitTimers[key] = null;
+    statsEmitter.emit(event);
+  }, delayMs);
+  statsEmitTimers[key]?.unref?.();
+}
+
 function getLocalDateKey(timestamp) {
   const d = timestamp ? new Date(timestamp) : new Date();
   return `${d.getFullYear()}-${String(d.getMonth() + 1).padStart(2, "0")}-${String(d.getDate()).padStart(2, "0")}`;
@@ -178,7 +190,7 @@ export function trackPendingRequest(model, provider, connectionId, started, erro
       if (connectionId && pendingRequests.byAccount[connectionId]?.[modelKey] > 0) {
         pendingRequests.byAccount[connectionId][modelKey] = 0;
       }
-      statsEmitter.emit("pending");
+      scheduleStatsEvent("pending");
     }, PENDING_TIMEOUT_MS);
   } else {
     clearTimeout(pendingTimers[timerKey]);
@@ -192,7 +204,7 @@ export function trackPendingRequest(model, provider, connectionId, started, erro
 
   const t = new Date().toLocaleTimeString("en-US", { hour12: false, hour: "2-digit", minute: "2-digit", second: "2-digit" });
   console.log(`[${t}] [PENDING] ${started ? "START" : "END"}${error ? " (ERROR)" : ""} | provider=${provider} | model=${model}`);
-  statsEmitter.emit("pending");
+  scheduleStatsEvent("pending");
 }
 
 export async function getActiveRequests() {
@@ -251,9 +263,35 @@ export async function saveRequestUsage(entry) {
     const promptTokens = tokens.prompt_tokens || tokens.input_tokens || 0;
     const completionTokens = tokens.completion_tokens || tokens.output_tokens || 0;
 
+    let inserted = false;
+
     // All 3 writes (history insert, daily upsert, lifetime counter) in ONE transaction.
     // better-sqlite3 is sync → no JS yield mid-transaction → no race in same process.
     db.transaction(() => {
+      const existing = db.get(
+        `SELECT id, endpoint FROM usageHistory
+         WHERE timestamp = ?
+           AND COALESCE(provider, '') = COALESCE(?, '')
+           AND COALESCE(model, '') = COALESCE(?, '')
+           AND COALESCE(connectionId, '') = COALESCE(?, '')
+           AND COALESCE(apiKey, '') = COALESCE(?, '')
+           AND promptTokens = ?
+           AND completionTokens = ?
+         ORDER BY id DESC LIMIT 1`,
+        [
+          entry.timestamp, entry.provider || null, entry.model || null,
+          entry.connectionId || null, entry.apiKey || null,
+          promptTokens, completionTokens,
+        ]
+      );
+
+      if (existing) {
+        if (!existing.endpoint && entry.endpoint) {
+          db.run(`UPDATE usageHistory SET endpoint = ? WHERE id = ?`, [entry.endpoint, existing.id]);
+        }
+        return;
+      }
+
       db.run(
         `INSERT INTO usageHistory(timestamp, provider, model, connectionId, apiKey, endpoint, promptTokens, completionTokens, cost, status, tokens, meta) VALUES(?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
         [
@@ -277,10 +315,13 @@ export async function saveRequestUsage(entry) {
       const cur = db.get(`SELECT value FROM _meta WHERE key = 'totalRequestsLifetime'`);
       const next = (cur ? parseInt(cur.value, 10) : 0) + 1;
       db.run(`INSERT INTO _meta(key, value) VALUES('totalRequestsLifetime', ?) ON CONFLICT(key) DO UPDATE SET value = excluded.value`, [String(next)]);
+      inserted = true;
     });
 
-    pushToRing(entry);
-    statsEmitter.emit("update");
+    if (inserted) {
+      pushToRing(entry);
+      scheduleStatsEvent("update", 250);
+    }
   } catch (e) {
     console.error("Failed to save usage stats:", e);
   }
diff --git a/src/sse/utils/logger.js b/src/sse/utils/logger.js
index d8127086..bb47ba5d 100644
--- a/src/sse/utils/logger.js
+++ b/src/sse/utils/logger.js
@@ -7,7 +7,7 @@ const LOG_LEVELS = {
   ERROR: 3
 };
 
-const LEVEL = LOG_LEVELS.DEBUG;
+const LEVEL = LOG_LEVELS[process.env.LOG_LEVEL?.toUpperCase?.()] ?? LOG_LEVELS.INFO;
 
 function formatTime() {
   return new Date().toLocaleTimeString("en-US", { hour12: false });
@@ -72,4 +72,3 @@ export function maskKey(key) {
   if (!key || key.length < 8) return "***";
   return `${key.slice(0, 4)}...${key.slice(-4)}`;
 }
-