ofrobots

It made the back button useless for me.

This profiler is sampling based. It takes a sample once every 512KiB allocated (on average, randomized) and reports all the allocations still alive at the end of the interval. So, yes it reports the subset of allocations that are sampled and are 'leaking' from the interval. In that sense it is better at finding memory leaks.

If you want to look at all the allocations during the interval, then you can use the 'Allocation timeline' profile – this will give you all the allocations but note that this might have significant overhead.

Recent versions of Chrome DevTools have a new profiling feature called 'Record allocation profile' that may help. Enable this around a few of the sawtooth and it will give you a profile based on a sampling of allocations that happen during that period. The profile will include the stack-trace at the time of the allocation which should help you figure out where the allocations are coming from.

The plan is for a Node.js 6.0 release on Tuesday: https://github.com/nodejs/node/issues/5766#issuecomment-1983.... This would include V8 5.0.

To be precise, Node.js 6.x will include V8 5.0. There has been a little discussion on being able to include V8 5.1 down the road, maybe, but there is nothing concrete on it at this point.

Also, the fate for tail-call-elimination is pretty uncertain at the moment; see: https://github.com/tc39/proposal-ptc-syntax

> 1 line of COBOL

Offtopic, but this would be quite a challenge.

Never use a single workload as a predictor of performance of the universe of all other workloads. The best benchmark is not a benchmark at all – it is your actual workload.

Yeah, 'ship' means different things in different contexts. In the context of your original comment, node stable is getting arrow functions within a week of Chrome stable getting them.

In general, io.js has been very good at picking up stable V8 soon after it ships in Chrome. The exception was V8 4.3, which was not picked up because of API compatibility issues.

This is not a problem for Chrome because chrome doesn't expose the V8 C++ API to large body of third party module writers like Node does. It takes time to deal with some API changes.

This is not really accurate. Arrow functions shipped in Chrome on Tuesday (Sep 1) with Chrome 45 (V8 4.5).

Congrats on the public announce of your 'secret' project! When do you release the code publicly? It would be great to be able to hack on it again.