//
	// This moment represents peak heap in use because we're
	// about to start sweeping.
	mheap_.pages.scav.index.nextGen()

	// Release the CPU limiter.
	gcCPULimiter.finishGCTransition(now)

	// Finish the current heap profiling cycle and start a new
	// heap profiling cycle. We do this before starting the world
	// so events don't leak into the wrong cycle.
	mProf_NextCycle()

	// The minimum trigger constant was chosen empirically: given a sufficiently
	// fast/scalable allocator with 48 Ps that could drive the trigger ratio
	// to <0.05, this constant causes applications to retain the same peak
	// RSS compared to not having this allocator.
	minTriggerRatioNum = 45 // ~0.7

	// The maximum trigger constant is chosen somewhat arbitrarily, but the
	// current constant has served us well over the years.

    }

    // De-cluster Fill ops that are
    //  - used at least once outside the cluster, and
    //  - not used inside the cluster.
    //
    // In this case, using XLA for the op can only make peak memory usage worse.
    // If we don't cluster the Fill, it can be materialized right before it's
    // used in the TF graph.  Whereas if we do cluster it, the Fill must be live

- All tasks run in parallel by default, subject to dependency constraints.
- Dependency resolution is cached.
- Configuration state and dependency resolution state is discarded from heap after writing the task graph. This reduces the peak heap usage required for a given set of tasks.

[[config_cache:in_action]]
=== Configuration caching in action

// TODO-RC redo demo so it no longer shows as incubating
image::configuration-cache/running-help.gif[]

		ctxt.Logf("archive: %s\n", strings.Join(argv, " "))
	}

	// If supported, use syscall.Exec() to invoke the archive command,
	// which should be the final remaining step needed for the link.
	// This will reduce peak RSS for the link (and speed up linking of
	// large applications), since when the archive command runs we
	// won't be holding onto all of the linker's live memory.
	if syscallExecSupported && !ownTmpDir {

    }
    if (builder.getKeyStrength() == Strength.WEAK
        && builder.getValueStrength() == Strength.STRONG) {
      return new MapMakerInternalMap<>(builder, WeakKeyDummyValueEntry.Helper.<K>instance());
    }
    if (builder.getValueStrength() == Strength.WEAK) {
      throw new IllegalArgumentException("Map cannot have both weak and dummy values");
    }
    throw new AssertionError();
  }

    }
    if (builder.getKeyStrength() == Strength.WEAK
        && builder.getValueStrength() == Strength.STRONG) {
      return new MapMakerInternalMap<>(builder, WeakKeyDummyValueEntry.Helper.<K>instance());
    }
    if (builder.getValueStrength() == Strength.WEAK) {
      throw new IllegalArgumentException("Map cannot have both weak and dummy values");
    }
    throw new AssertionError();
  }

	}
	if _, err := buf.Peek(1); err != io.EOF {
		t.Fatalf("want EOF got %v", err)
	}

	// Test for issue 3022, not exposing a reader's error on a successful Peek.
	buf = NewReaderSize(dataAndEOFReader("abcd"), 32)
	if s, err := buf.Peek(2); string(s) != "ab" || err != nil {
		t.Errorf(`Peek(2) on "abcd", EOF = %q, %v; want "ab", nil`, string(s), err)
	}
	if s, err := buf.Peek(4); string(s) != "abcd" || err != nil {

	unlock(&mheap_.speciallock)
}

// The described object has a weak pointer.
//
// Weak pointers in the GC have the following invariants:
//
//   - Strong-to-weak conversions must ensure the strong pointer
//     remains live until the weak handle is installed. This ensures
//     that creating a weak pointer cannot fail.
//
//   - Weak-to-strong conversions require the weakly-referenced

   *     Iterators.peekingIterator(Iterators.forArray("a", "b"));
   * String a1 = peekingIterator.peek(); // returns "a"
   * String a2 = peekingIterator.peek(); // also returns "a"
   * String a3 = peekingIterator.next(); // also returns "a"
   * }</pre>
   *
   * <p>Any structural changes to the underlying iteration (aside from those performed by the