1 files changed, 30 insertions, 15 deletions

diff --git a/ui/src/tracks/cpu_slices/controller.ts b/ui/src/tracks/cpu_slices/controller.ts
index 278450e23..5917968be 100644
--- a/ui/src/tracks/cpu_slices/controller.ts
+++ b/ui/src/tracks/cpu_slices/controller.ts
@@ -12,9 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-import {fromNs, toNs} from '../../common/time';
-import {LIMIT} from '../../common/track_data';
-
+import {fromNs} from '../../common/time';
 import {
   TrackController,
   trackControllerRegistry
@@ -30,13 +28,22 @@ import {
 
 class CpuSliceTrackController extends TrackController<Config, Data> {
   static readonly kind = CPU_SLICE_TRACK_KIND;
+  private busy = false;
   private setup = false;
 
-  async onBoundsChange(start: number, end: number, resolution: number):
-      Promise<Data> {
-    const startNs = toNs(start);
-    const endNs = toNs(end);
+  onBoundsChange(start: number, end: number, resolution: number): void {
+    this.update(start, end, resolution);
+  }
+
+  private async update(start: number, end: number, resolution: number):
+      Promise<void> {
+    // TODO: we should really call TraceProcessor.Interrupt() at this point.
+    if (this.busy) return;
 
+    const startNs = Math.round(start * 1e9);
+    const endNs = Math.round(end * 1e9);
+
+    this.busy = true;
     if (this.setup === false) {
       await this.query(
           `create virtual table ${this.tableName('window')} using window;`);
@@ -62,18 +69,20 @@ class CpuSliceTrackController extends TrackController<Config, Data> {
       where rowid = 0;`);
 
     if (isQuantized) {
-      return this.computeSummary(
-          fromNs(windowStartNs), end, resolution, bucketSizeNs);
+      this.publish(await this.computeSummary(
+          fromNs(windowStartNs), end, resolution, bucketSizeNs));
     } else {
-      return this.computeSlices(fromNs(windowStartNs), end, resolution);
+      this.publish(
+          await this.computeSlices(fromNs(windowStartNs), end, resolution));
     }
+    this.busy = false;
   }
 
   private async computeSummary(
       start: number, end: number, resolution: number,
       bucketSizeNs: number): Promise<SummaryData> {
-    const startNs = toNs(start);
-    const endNs = toNs(end);
+    const startNs = Math.round(start * 1e9);
+    const endNs = Math.round(end * 1e9);
     const numBuckets = Math.ceil((endNs - startNs) / bucketSizeNs);
 
     const query = `select
@@ -82,7 +91,7 @@ class CpuSliceTrackController extends TrackController<Config, Data> {
         from ${this.tableName('span')}
         where cpu = ${this.config.cpu}
         and utid != 0
-        group by quantum_ts limit ${LIMIT}`;
+        group by quantum_ts`;
 
     const rawResult = await this.query(query);
     const numRows = +rawResult.numRecords;
@@ -92,7 +101,6 @@ class CpuSliceTrackController extends TrackController<Config, Data> {
       start,
       end,
       resolution,
-      length: numRows,
       bucketSizeSeconds: fromNs(bucketSizeNs),
       utilizations: new Float64Array(numBuckets),
     };
@@ -121,7 +129,6 @@ class CpuSliceTrackController extends TrackController<Config, Data> {
       start,
       end,
       resolution,
-      length: numRows,
       ids: new Float64Array(numRows),
       starts: new Float64Array(numRows),
       ends: new Float64Array(numRows),
@@ -142,6 +149,14 @@ class CpuSliceTrackController extends TrackController<Config, Data> {
     return slices;
   }
 
+  private async query(query: string) {
+    const result = await this.engine.query(query);
+    if (result.error) {
+      console.error(`Query error "${query}": ${result.error}`);
+      throw new Error(`Query error "${query}": ${result.error}`);
+    }
+    return result;
+  }
 
   onDestroy(): void {
     if (this.setup) {