Memory-takeCensus-10.js

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// Check counts produced by takeCensus.

//

// Note that tracking allocation sites adds unique IDs to objects which

// increases their size, making it hard to test reported sizes exactly.

let g = newGlobal({newCompartment: true});

let dbg = new Debugger(g);

let sizeOfAM = byteSize(allocationMarker());

// Allocate a single allocation marker, and check that we can find it.

g.eval('var hold = allocationMarker();');

let census = dbg.memory.takeCensus({ breakdown: { by: 'objectClass' } });

assertEq(census.AllocationMarker.count, 1);

assertEq(census.AllocationMarker.bytes, sizeOfAM);

g.evaluate(`

           var objs = [];

           function fnerd() {

             objs.push(allocationMarker());

             for (let i = 0; i < 10; i++)

               objs.push(allocationMarker());

`,

           { fileName: 'J. Edgar Hoover', lineNumber: 2000 });

dbg.memory.allocationSamplingProbability = 1;

dbg.memory.trackingAllocationSites = true;

g.hold = null;

g.fnerd();

census = dbg.memory.takeCensus({

  breakdown: { by: 'objectClass',

               then: { by: 'allocationStack' }

});

let seen = 0;

census.AllocationMarker.forEach((v, k) => {

  assertEq(k.functionDisplayName, 'fnerd');

  assertEq(k.source, 'J. Edgar Hoover');

  switch (k.line) {

  case 2003:

    assertEq(v.count, 1);

    assertEq(v.bytes >= sizeOfAM, true);

    seen++;

    break;

  case 2005:

    assertEq(v.count, 10);

    assertEq(v.bytes >= 10 * sizeOfAM, true);

    seen++;

    break;

  default: assertEq(true, false);

});

assertEq(seen, 2);