[dbg_nsk]

Absolutely agree with you about finalizers! However, please note that this "threadReaper" code is from JDK class, so, the problem can appear on every application that just use Timer class.

Of course, there are many other examples of false-roots, but this concrete class caused unexpected OOMs on several applications of our clients, so we made this small sample and used it for sanity checking during implementing precise GC (and then mentioned it in the post).

[yxhuvud]

I take it you are part of the ones behind the article? Did you ever see the papers about a conservative variant of immix, which would be both compacting and conservative?

[dbg_nsk]

Yes, I wrote this article.

No, I haven't read those papers before, but after your comment I took a look at one of them.. and it is very interesting! Thanks for mentioning it.

But, if I understood correctly, the excess memory retention is still a problem in conservative immix?

[yxhuvud]

It is mentioned in one of the papers (or possibly the doctoral thesis, which is nice as it gives an overview of the whole chain of improvements) that it can still happen but that it is much better compared to what they benchmarked it against (boehm, iirc). Hard to tell if it delivers what it promises though..

[dbg_nsk]

It would be very interesting to run our sample with Timers on this GC. In that paper I found a link to their implementation, but unfortunately it is unavailable.

[yxhuvud]

Link is dead, but code is on Github somewhere. Dunno where I found the link to it but I am away from computer for a few days so I can't really look it up for you.

[barrkel]

I didn't know it was from the JDK, interesting.