lts/deps/v8/tools/heap-stats/model.js
// Copyright 2018 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
'use strict';
class Isolate {
constructor(address) {
this.address = address;
this.start = null;
this.end = null;
this.samples = Object.create(null);
this.non_empty_instance_types = new Set();
this.gcs = Object.create(null);
this.zonetags = [];
this.samples = {zone: {}};
this.data_sets = new Set();
this.peakMemory = 0;
// Maps instance_types to their max memory consumption over all gcs.
this.instanceTypePeakMemory = Object.create(null);
// Peak memory consumed by any single instance type.
this.singleInstanceTypePeakMemory = 0;
}
finalize() {
Object.values(this.gcs).forEach(gc => this.finalizeGC(gc));
this.sortInstanceTypePeakMemory();
}
getLabel() {
let label = `${this.address}: gc=#${Object.keys(this.gcs).length}`;
label += ` peak=${formatBytes(this.peakMemory)}`
return label;
}
finalizeGC(gc_data) {
this.data_sets.forEach(key => this.finalizeDataSet(gc_data[key]));
if (!('live' in gc_data)) return;
let liveData = gc_data.live;
this.peakMemory = Math.max(this.peakMemory, liveData.overall);
let data = liveData.instance_type_data;
for (let name in data) {
let prev = this.instanceTypePeakMemory[name] || 0;
this.instanceTypePeakMemory[name] = Math.max(prev, data[name].overall);
}
}
finalizeDataSet(data_set) {
// Create a ranked instance type array that sorts instance types by
// memory size (overall).
let data = data_set.instance_type_data;
let ranked_instance_types =
[...data_set.non_empty_instance_types].sort((a, b) => {
return data[a].overall - data[b].overall;
});
// Reassemble the instance_type list sorted by size.
let sorted_data = Object.create(null);
let max = 0;
ranked_instance_types.forEach((name) => {
let entry = sorted_data[name] = data[name];
max = Math.max(max, entry.overall);
});
data_set.instance_type_data = data;
data_set.singleInstancePeakMemory = max;
Object.entries(data_set.instance_type_data).forEach(([name, entry]) => {
this.checkHistogram(
name, entry, data_set.bucket_sizes, 'histogram', ' overall');
this.checkHistogram(
name, entry, data_set.bucket_sizes, 'over_allocated_histogram',
' over_allocated');
});
}
// Check that a lower bound for histogram memory does not exceed the
// overall counter.
checkHistogram(type, entry, bucket_sizes, histogram, overallProperty) {
let sum = 0;
for (let i = 1; i < entry[histogram].length; i++) {
sum += entry[histogram][i] * bucket_sizes[i - 1];
}
const overall = entry[overallProperty];
if (sum >= overall) {
console.error(
`${type}: sum('${histogram}') > overall (${sum} > ${overall})`);
}
}
sortInstanceTypePeakMemory() {
let entries = Object.entries(this.instanceTypePeakMemory);
entries.sort((a, b) => {return b[1] - a[1]});
this.instanceTypePeakMemory = Object.create(null);
let max = 0;
for (let [key, value] of entries) {
this.instanceTypePeakMemory[key] = value;
max = Math.max(max, value);
}
this.singleInstanceTypePeakMemory = max;
}
getInstanceTypePeakMemory(type) {
if (!(type in this.instanceTypePeakMemory)) return 0;
return this.instanceTypePeakMemory[type];
}
}