ui/src/controller/heap_profile_controller.ts - platform/external/perfetto - Git at Google

 // Copyright (C) 2019 The Android Open Source Project
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //      http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.

 import {Engine} from '../common/engine';
 import {
   ALLOC_SPACE_MEMORY_ALLOCATED_KEY,
   DEFAULT_VIEWING_OPTION,
   expandCallsites,
   findRootSize,
   mergeCallsites,
   OBJECTS_ALLOCATED_KEY,
   OBJECTS_ALLOCATED_NOT_FREED_KEY,
   SPACE_MEMORY_ALLOCATED_NOT_FREED_KEY
 } from '../common/flamegraph_util';
 import {CallsiteInfo, HeapProfileFlamegraph} from '../common/state';
 import {fromNs} from '../common/time';
 import {HeapProfileDetails} from '../frontend/globals';

 import {Controller} from './controller';
 import {globals} from './globals';

 export interface HeapProfileControllerArgs {
   engine: Engine;
 }
 const MIN_PIXEL_DISPLAYED = 1;

 class TablesCache {
   private engine: Engine;
   private cache: Map<string, string>;
   private prefix: string;
   private tableId: number;
   private cacheSizeLimit: number;

   constructor(engine: Engine, prefix: string) {
     this.engine = engine;
     this.cache = new Map<string, string>();
     this.prefix = prefix;
     this.tableId = 0;
     this.cacheSizeLimit = 10;
   }

   async getTableName(query: string): Promise<string> {
     let tableName = this.cache.get(query);
     if (tableName === undefined) {
       // TODO(hjd): This should be LRU.
       if (this.cache.size > this.cacheSizeLimit) {
         for (const name of this.cache.values()) {
           await this.engine.query(`drop table ${name}`);
         }
         this.cache.clear();
       }
       tableName = `${this.prefix}_${this.tableId++}`;
       await this.engine.query(
           `create temp table if not exists ${tableName} as ${query}`);
       this.cache.set(query, tableName);
     }
     return tableName;
   }
 }

 export class HeapProfileController extends Controller<'main'> {
   private flamegraphDatasets: Map<string, CallsiteInfo[]> = new Map();
   private lastSelectedHeapProfile?: HeapProfileFlamegraph;
   private requestingData = false;
   private queuedRequest = false;
   private heapProfileDetails: HeapProfileDetails = {};
   private cache: TablesCache;

   constructor(private args: HeapProfileControllerArgs) {
     super('main');
     this.cache = new TablesCache(args.engine, 'grouped_callsites');
   }

   run() {
     const selection = globals.state.currentHeapProfileFlamegraph;

     if (!selection) return;

     if (this.shouldRequestData(selection)) {
       if (this.requestingData) {
         this.queuedRequest = true;
       } else {
         this.requestingData = true;
         const selectedHeapProfile: HeapProfileFlamegraph =
             this.copyHeapProfile(selection);

         this.getHeapProfileMetadata(
                 selection.type,
                 selectedHeapProfile.ts,
                 selectedHeapProfile.upid)
             .then(result => {
               if (result !== undefined) {
                 Object.assign(this.heapProfileDetails, result);
               }

               // TODO(hjd): Clean this up.
               if (this.lastSelectedHeapProfile &&
                   this.lastSelectedHeapProfile.focusRegex !==
                       selection.focusRegex) {
                 this.flamegraphDatasets.clear();
               }

               this.lastSelectedHeapProfile = this.copyHeapProfile(selection);

               const expandedId = selectedHeapProfile.expandedCallsite ?
                   selectedHeapProfile.expandedCallsite.id :
                   -1;
               const rootSize =
                   selectedHeapProfile.expandedCallsite === undefined ?
                   undefined :
                   selectedHeapProfile.expandedCallsite.totalSize;

               const key =
                   `${selectedHeapProfile.upid};${selectedHeapProfile.ts}`;

               this.getFlamegraphData(
                       key,
                       selectedHeapProfile.viewingOption ?
                           selectedHeapProfile.viewingOption :
                           DEFAULT_VIEWING_OPTION,
                       selection.ts,
                       selectedHeapProfile.upid,
                       selectedHeapProfile.type,
                       selectedHeapProfile.focusRegex)
                   .then(flamegraphData => {
                     if (flamegraphData !== undefined && selection &&
                         selection.kind === selectedHeapProfile.kind &&
                         selection.id === selectedHeapProfile.id &&
                         selection.ts === selectedHeapProfile.ts) {
                       const expandedFlamegraphData =
                           expandCallsites(flamegraphData, expandedId);
                       this.prepareAndMergeCallsites(
                           expandedFlamegraphData,
                           this.lastSelectedHeapProfile!.viewingOption,
                           rootSize,
                           this.lastSelectedHeapProfile!.expandedCallsite);
                     }
                   })
                   .finally(() => {
                     this.requestingData = false;
                     if (this.queuedRequest) {
                       this.queuedRequest = false;
                       this.run();
                     }
                   });
             });
       }
     }
   }

   private copyHeapProfile(heapProfile: HeapProfileFlamegraph):
       HeapProfileFlamegraph {
     return {
       kind: heapProfile.kind,
       id: heapProfile.id,
       upid: heapProfile.upid,
       ts: heapProfile.ts,
       type: heapProfile.type,
       expandedCallsite: heapProfile.expandedCallsite,
       viewingOption: heapProfile.viewingOption,
       focusRegex: heapProfile.focusRegex,
     };
   }

   private shouldRequestData(selection: HeapProfileFlamegraph) {
     return selection.kind === 'HEAP_PROFILE_FLAMEGRAPH' &&
         (this.lastSelectedHeapProfile === undefined ||
          (this.lastSelectedHeapProfile !== undefined &&
           (this.lastSelectedHeapProfile.id !== selection.id ||
            this.lastSelectedHeapProfile.ts !== selection.ts ||
            this.lastSelectedHeapProfile.type !== selection.type ||
            this.lastSelectedHeapProfile.upid !== selection.upid ||
            this.lastSelectedHeapProfile.viewingOption !==
                selection.viewingOption ||
            this.lastSelectedHeapProfile.focusRegex !== selection.focusRegex ||
            this.lastSelectedHeapProfile.expandedCallsite !==
                selection.expandedCallsite)));
   }

   private prepareAndMergeCallsites(
       flamegraphData: CallsiteInfo[],
       viewingOption: string|undefined = DEFAULT_VIEWING_OPTION,
       rootSize?: number, expandedCallsite?: CallsiteInfo) {
     const mergedFlamegraphData = mergeCallsites(
         flamegraphData, this.getMinSizeDisplayed(flamegraphData, rootSize));
     this.heapProfileDetails.flamegraph = mergedFlamegraphData;
     this.heapProfileDetails.expandedCallsite = expandedCallsite;
     this.heapProfileDetails.viewingOption = viewingOption;
     globals.publish('HeapProfileDetails', this.heapProfileDetails);
   }


   async getFlamegraphData(
       baseKey: string, viewingOption: string, ts: number, upid: number,
       type: string, focusRegex: string): Promise<CallsiteInfo[]> {
     let currentData: CallsiteInfo[];
     const key = `${baseKey}-${viewingOption}`;
     if (this.flamegraphDatasets.has(key)) {
       currentData = this.flamegraphDatasets.get(key)!;
     } else {
       // TODO(taylori): Show loading state.

       // Collecting data for drawing flamegraph for selected heap profile.
       // Data needs to be in following format:
       // id, name, parent_id, depth, total_size
       const tableName =
           await this.prepareViewsAndTables(ts, upid, type, focusRegex);
       currentData =
           await this.getFlamegraphDataFromTables(tableName, viewingOption);
       this.flamegraphDatasets.set(key, currentData);
     }
     return currentData;
   }

   async getFlamegraphDataFromTables(
       tableName: string, viewingOption = DEFAULT_VIEWING_OPTION) {
     let orderBy = '';
     let sizeIndex = 4;
     let selfIndex = 9;
     // TODO(fmayer): Improve performance so this is no longer necessary.
     // Alternatively consider collapsing frames of the same label.
     const maxDepth = 100;
     switch (viewingOption) {
       case SPACE_MEMORY_ALLOCATED_NOT_FREED_KEY:
         orderBy = `where cumulative_size > 0 and depth < ${
             maxDepth} order by depth, parent_id,
             cumulative_size desc, name`;
         sizeIndex = 4;
         selfIndex = 9;
         break;
       case ALLOC_SPACE_MEMORY_ALLOCATED_KEY:
         orderBy = `where cumulative_alloc_size > 0 and depth < ${
             maxDepth} order by depth, parent_id,
             cumulative_alloc_size desc, name`;
         sizeIndex = 5;
         selfIndex = 9;
         break;
       case OBJECTS_ALLOCATED_NOT_FREED_KEY:
         orderBy = `where cumulative_count > 0 and depth < ${
             maxDepth} order by depth, parent_id,
             cumulative_count desc, name`;
         sizeIndex = 6;
         selfIndex = 10;
         break;
       case OBJECTS_ALLOCATED_KEY:
         orderBy = `where cumulative_alloc_count > 0 and depth < ${
             maxDepth} order by depth, parent_id,
             cumulative_alloc_count desc, name`;
         sizeIndex = 7;
         selfIndex = 10;
         break;
       default:
         break;
     }

     const callsites = await this.args.engine.query(
         `SELECT id, IFNULL(DEMANGLE(name), name), IFNULL(parent_id, -1), depth,
         cumulative_size, cumulative_alloc_size, cumulative_count,
         cumulative_alloc_count, map_name, size, count from ${tableName} ${
             orderBy}`);

     const flamegraphData: CallsiteInfo[] = new Array();
     const hashToindex: Map<number, number> = new Map();
     for (let i = 0; i < callsites.numRecords; i++) {
       const hash = callsites.columns[0].longValues![i];
       let name = callsites.columns[1].stringValues![i];
       const parentHash = callsites.columns[2].longValues![i];
       const depth = +callsites.columns[3].longValues![i];
       const totalSize = +callsites.columns[sizeIndex].longValues![i];
       const mapping = callsites.columns[8].stringValues![i];
       const selfSize = +callsites.columns[selfIndex].longValues![i];
       const parentId =
           hashToindex.has(+parentHash) ? hashToindex.get(+parentHash)! : -1;
       if (depth === maxDepth - 1) {
         name += ' [tree truncated]';
       }
       hashToindex.set(+hash, i);
       // Instead of hash, we will store index of callsite in this original array
       // as an id of callsite. That way, we have quicker access to parent and it
       // will stay unique.
       flamegraphData.push({
         id: i,
         totalSize,
         depth,
         parentId,
         name,
         selfSize,
         mapping,
         merged: false
       });
     }
     return flamegraphData;
   }

   private async prepareViewsAndTables(
       ts: number, upid: number, type: string,
       focusRegex: string): Promise<string> {
     // Creating unique names for views so we can reuse and not delete them
     // for each marker.
     let whereClause = '';
     if (focusRegex !== '') {
       whereClause = `where focus_str = '${focusRegex}'`;
     }

     return this.cache.getTableName(
         `select id, name, map_name, parent_id, depth, cumulative_size,
           cumulative_alloc_size, cumulative_count, cumulative_alloc_count,
           size, alloc_size, count, alloc_count
           from experimental_flamegraph(${ts}, ${upid}, '${type}') ${
             whereClause}`);
   }

   getMinSizeDisplayed(flamegraphData: CallsiteInfo[], rootSize?: number):
       number {
     const timeState = globals.state.frontendLocalState.visibleState;
     const width =
         (timeState.endSec - timeState.startSec) / timeState.resolution;
     if (rootSize === undefined) {
       rootSize = findRootSize(flamegraphData);
     }
     return MIN_PIXEL_DISPLAYED * rootSize / width;
   }

   async getHeapProfileMetadata(type: string, ts: number, upid: number) {
     // Don't do anything if selection of the marker stayed the same.
     if ((this.lastSelectedHeapProfile !== undefined &&
          ((this.lastSelectedHeapProfile.ts === ts &&
            this.lastSelectedHeapProfile.upid === upid)))) {
       return undefined;
     }

     // Collecting data for more information about heap profile, such as:
     // total memory allocated, memory that is allocated and not freed.
     const pidValue = await this.args.engine.query(
         `select pid from process where upid = ${upid}`);
     const pid = pidValue.columns[0].longValues![0];
     const startTime = fromNs(ts) - globals.state.traceTime.startSec;
     return {ts: startTime, tsNs: ts, pid, upid, type};
   }
 }
	// Copyright (C) 2019 The Android Open Source Project
	//
	// Licensed under the Apache License, Version 2.0 (the "License");
	// you may not use this file except in compliance with the License.
	// You may obtain a copy of the License at
	//
	// http://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing, software
	// distributed under the License is distributed on an "AS IS" BASIS,
	// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	// See the License for the specific language governing permissions and
	// limitations under the License.

	import {Engine} from '../common/engine';
	import {
	ALLOC_SPACE_MEMORY_ALLOCATED_KEY,
	DEFAULT_VIEWING_OPTION,
	expandCallsites,
	findRootSize,
	mergeCallsites,
	OBJECTS_ALLOCATED_KEY,
	OBJECTS_ALLOCATED_NOT_FREED_KEY,
	SPACE_MEMORY_ALLOCATED_NOT_FREED_KEY
	} from '../common/flamegraph_util';
	import {CallsiteInfo, HeapProfileFlamegraph} from '../common/state';
	import {fromNs} from '../common/time';
	import {HeapProfileDetails} from '../frontend/globals';

	import {Controller} from './controller';
	import {globals} from './globals';

	export interface HeapProfileControllerArgs {
	engine: Engine;
	}
	const MIN_PIXEL_DISPLAYED = 1;

	class TablesCache {
	private engine: Engine;
	private cache: Map<string, string>;
	private prefix: string;
	private tableId: number;
	private cacheSizeLimit: number;

	constructor(engine: Engine, prefix: string) {
	this.engine = engine;
	this.cache = new Map<string, string>();
	this.prefix = prefix;
	this.tableId = 0;
	this.cacheSizeLimit = 10;
	}

	async getTableName(query: string): Promise<string> {
	let tableName = this.cache.get(query);
	if (tableName === undefined) {
	// TODO(hjd): This should be LRU.
	if (this.cache.size > this.cacheSizeLimit) {
	for (const name of this.cache.values()) {
	await this.engine.query(`drop table ${name}`);
	}
	this.cache.clear();
	}
	tableName = `${this.prefix}_${this.tableId++}`;
	await this.engine.query(
	`create temp table if not exists ${tableName} as ${query}`);
	this.cache.set(query, tableName);
	}
	return tableName;
	}
	}

	export class HeapProfileController extends Controller<'main'> {
	private flamegraphDatasets: Map<string, CallsiteInfo[]> = new Map();
	private lastSelectedHeapProfile?: HeapProfileFlamegraph;
	private requestingData = false;
	private queuedRequest = false;
	private heapProfileDetails: HeapProfileDetails = {};
	private cache: TablesCache;

	constructor(private args: HeapProfileControllerArgs) {
	super('main');
	this.cache = new TablesCache(args.engine, 'grouped_callsites');
	}

	run() {
	const selection = globals.state.currentHeapProfileFlamegraph;

	if (!selection) return;

	if (this.shouldRequestData(selection)) {
	if (this.requestingData) {
	this.queuedRequest = true;
	} else {
	this.requestingData = true;
	const selectedHeapProfile: HeapProfileFlamegraph =
	this.copyHeapProfile(selection);

	this.getHeapProfileMetadata(
	selection.type,
	selectedHeapProfile.ts,
	selectedHeapProfile.upid)
	.then(result => {
	if (result !== undefined) {
	Object.assign(this.heapProfileDetails, result);
	}

	// TODO(hjd): Clean this up.
	if (this.lastSelectedHeapProfile &&
	this.lastSelectedHeapProfile.focusRegex !==
	selection.focusRegex) {
	this.flamegraphDatasets.clear();
	}

	this.lastSelectedHeapProfile = this.copyHeapProfile(selection);

	const expandedId = selectedHeapProfile.expandedCallsite ?
	selectedHeapProfile.expandedCallsite.id :
	-1;
	const rootSize =
	selectedHeapProfile.expandedCallsite === undefined ?
	undefined :
	selectedHeapProfile.expandedCallsite.totalSize;

	const key =
	`${selectedHeapProfile.upid};${selectedHeapProfile.ts}`;

	this.getFlamegraphData(
	key,
	selectedHeapProfile.viewingOption ?
	selectedHeapProfile.viewingOption :
	DEFAULT_VIEWING_OPTION,
	selection.ts,
	selectedHeapProfile.upid,
	selectedHeapProfile.type,
	selectedHeapProfile.focusRegex)
	.then(flamegraphData => {
	if (flamegraphData !== undefined && selection &&
	selection.kind === selectedHeapProfile.kind &&
	selection.id === selectedHeapProfile.id &&
	selection.ts === selectedHeapProfile.ts) {
	const expandedFlamegraphData =
	expandCallsites(flamegraphData, expandedId);
	this.prepareAndMergeCallsites(
	expandedFlamegraphData,
	this.lastSelectedHeapProfile!.viewingOption,
	rootSize,
	this.lastSelectedHeapProfile!.expandedCallsite);
	}
	})
	.finally(() => {
	this.requestingData = false;
	if (this.queuedRequest) {
	this.queuedRequest = false;
	this.run();
	}
	});
	});
	}
	}
	}

	private copyHeapProfile(heapProfile: HeapProfileFlamegraph):
	HeapProfileFlamegraph {
	return {
	kind: heapProfile.kind,
	id: heapProfile.id,
	upid: heapProfile.upid,
	ts: heapProfile.ts,
	type: heapProfile.type,
	expandedCallsite: heapProfile.expandedCallsite,
	viewingOption: heapProfile.viewingOption,
	focusRegex: heapProfile.focusRegex,
	};
	}

	private shouldRequestData(selection: HeapProfileFlamegraph) {
	return selection.kind === 'HEAP_PROFILE_FLAMEGRAPH' &&
	(this.lastSelectedHeapProfile === undefined \|\|
	(this.lastSelectedHeapProfile !== undefined &&
	(this.lastSelectedHeapProfile.id !== selection.id \|\|
	this.lastSelectedHeapProfile.ts !== selection.ts \|\|
	this.lastSelectedHeapProfile.type !== selection.type \|\|
	this.lastSelectedHeapProfile.upid !== selection.upid \|\|
	this.lastSelectedHeapProfile.viewingOption !==
	selection.viewingOption \|\|
	this.lastSelectedHeapProfile.focusRegex !== selection.focusRegex \|\|
	this.lastSelectedHeapProfile.expandedCallsite !==
	selection.expandedCallsite)));
	}

	private prepareAndMergeCallsites(
	flamegraphData: CallsiteInfo[],
	viewingOption: string\|undefined = DEFAULT_VIEWING_OPTION,
	rootSize?: number, expandedCallsite?: CallsiteInfo) {
	const mergedFlamegraphData = mergeCallsites(
	flamegraphData, this.getMinSizeDisplayed(flamegraphData, rootSize));
	this.heapProfileDetails.flamegraph = mergedFlamegraphData;
	this.heapProfileDetails.expandedCallsite = expandedCallsite;
	this.heapProfileDetails.viewingOption = viewingOption;
	globals.publish('HeapProfileDetails', this.heapProfileDetails);
	}


	async getFlamegraphData(
	baseKey: string, viewingOption: string, ts: number, upid: number,
	type: string, focusRegex: string): Promise<CallsiteInfo[]> {
	let currentData: CallsiteInfo[];
	const key = `${baseKey}-${viewingOption}`;
	if (this.flamegraphDatasets.has(key)) {
	currentData = this.flamegraphDatasets.get(key)!;
	} else {
	// TODO(taylori): Show loading state.

	// Collecting data for drawing flamegraph for selected heap profile.
	// Data needs to be in following format:
	// id, name, parent_id, depth, total_size
	const tableName =
	await this.prepareViewsAndTables(ts, upid, type, focusRegex);
	currentData =
	await this.getFlamegraphDataFromTables(tableName, viewingOption);
	this.flamegraphDatasets.set(key, currentData);
	}
	return currentData;
	}

	async getFlamegraphDataFromTables(
	tableName: string, viewingOption = DEFAULT_VIEWING_OPTION) {
	let orderBy = '';
	let sizeIndex = 4;
	let selfIndex = 9;
	// TODO(fmayer): Improve performance so this is no longer necessary.
	// Alternatively consider collapsing frames of the same label.
	const maxDepth = 100;
	switch (viewingOption) {
	case SPACE_MEMORY_ALLOCATED_NOT_FREED_KEY:
	orderBy = `where cumulative_size > 0 and depth < ${
	maxDepth} order by depth, parent_id,
	cumulative_size desc, name`;
	sizeIndex = 4;
	selfIndex = 9;
	break;
	case ALLOC_SPACE_MEMORY_ALLOCATED_KEY:
	orderBy = `where cumulative_alloc_size > 0 and depth < ${
	maxDepth} order by depth, parent_id,
	cumulative_alloc_size desc, name`;
	sizeIndex = 5;
	selfIndex = 9;
	break;
	case OBJECTS_ALLOCATED_NOT_FREED_KEY:
	orderBy = `where cumulative_count > 0 and depth < ${
	maxDepth} order by depth, parent_id,
	cumulative_count desc, name`;
	sizeIndex = 6;
	selfIndex = 10;
	break;
	case OBJECTS_ALLOCATED_KEY:
	orderBy = `where cumulative_alloc_count > 0 and depth < ${
	maxDepth} order by depth, parent_id,
	cumulative_alloc_count desc, name`;
	sizeIndex = 7;
	selfIndex = 10;
	break;
	default:
	break;
	}

	const callsites = await this.args.engine.query(
	`SELECT id, IFNULL(DEMANGLE(name), name), IFNULL(parent_id, -1), depth,
	cumulative_size, cumulative_alloc_size, cumulative_count,
	cumulative_alloc_count, map_name, size, count from ${tableName} ${
	orderBy}`);

	const flamegraphData: CallsiteInfo[] = new Array();
	const hashToindex: Map<number, number> = new Map();
	for (let i = 0; i < callsites.numRecords; i++) {
	const hash = callsites.columns[0].longValues![i];
	let name = callsites.columns[1].stringValues![i];
	const parentHash = callsites.columns[2].longValues![i];
	const depth = +callsites.columns[3].longValues![i];
	const totalSize = +callsites.columns[sizeIndex].longValues![i];
	const mapping = callsites.columns[8].stringValues![i];
	const selfSize = +callsites.columns[selfIndex].longValues![i];
	const parentId =
	hashToindex.has(+parentHash) ? hashToindex.get(+parentHash)! : -1;
	if (depth === maxDepth - 1) {
	name += ' [tree truncated]';
	}
	hashToindex.set(+hash, i);
	// Instead of hash, we will store index of callsite in this original array
	// as an id of callsite. That way, we have quicker access to parent and it
	// will stay unique.
	flamegraphData.push({
	id: i,
	totalSize,
	depth,
	parentId,
	name,
	selfSize,
	mapping,
	merged: false
	});
	}
	return flamegraphData;
	}

	private async prepareViewsAndTables(
	ts: number, upid: number, type: string,
	focusRegex: string): Promise<string> {
	// Creating unique names for views so we can reuse and not delete them
	// for each marker.
	let whereClause = '';
	if (focusRegex !== '') {
	whereClause = `where focus_str = '${focusRegex}'`;
	}

	return this.cache.getTableName(
	`select id, name, map_name, parent_id, depth, cumulative_size,
	cumulative_alloc_size, cumulative_count, cumulative_alloc_count,
	size, alloc_size, count, alloc_count
	from experimental_flamegraph(${ts}, ${upid}, '${type}') ${
	whereClause}`);
	}

	getMinSizeDisplayed(flamegraphData: CallsiteInfo[], rootSize?: number):
	number {
	const timeState = globals.state.frontendLocalState.visibleState;
	const width =
	(timeState.endSec - timeState.startSec) / timeState.resolution;
	if (rootSize === undefined) {
	rootSize = findRootSize(flamegraphData);
	}
	return MIN_PIXEL_DISPLAYED * rootSize / width;
	}

	async getHeapProfileMetadata(type: string, ts: number, upid: number) {
	// Don't do anything if selection of the marker stayed the same.
	if ((this.lastSelectedHeapProfile !== undefined &&
	((this.lastSelectedHeapProfile.ts === ts &&
	this.lastSelectedHeapProfile.upid === upid)))) {
	return undefined;
	}

	// Collecting data for more information about heap profile, such as:
	// total memory allocated, memory that is allocated and not freed.
	const pidValue = await this.args.engine.query(
	`select pid from process where upid = ${upid}`);
	const pid = pidValue.columns[0].longValues![0];
	const startTime = fromNs(ts) - globals.state.traceTime.startSec;
	return {ts: startTime, tsNs: ts, pid, upid, type};
	}
	}