On Wednesday, February 6, 2019 at 5:15:53 PM UTC+2, Alex Miller wrote: > > I think the condition here means that the loop compilation can't tell that > the s local is definitely out of scope and can be cleared, so you end up > holding the head. > > While there is some analysis here, we're not doing inference level stuff > on the "if false" to knock out branches etc and generally that's not the > kind of thing we try to do. >
I.e. WONTFIX? Using lazy sequences is or can be pretty dangerous without plenty and frequent testing, then -- since "don't hold onto the head" means one will have to take into account whatever code the compiler and/or libraries (c.c.async?) may or may not generate behind the scenes based on subtleties. Hmmmm ...anyway, I'll try to work around this; perhaps by avoiding lazy sequences altogether. For me switching to clojure.core.async and doing something like this *seems* to have worked (perhaps useful for others who find this thread later): - wrap the range (or infinite or long sequence really) in a *source* chan <https://clojuredocs.org/clojure.core.async/chan>. - do the transformation in a *middle* chan; noting that the chan Fn takes an xform arg. - pipe <https://clojuredocs.org/clojure.core.async/pipe> the *middle* chan to your final *output* chan. something like: *(async/pipe (handle-source-chan (async/chan 1000 xform) ...) output-chan)* ...it's a bit tricky to setup -- but yeah; no leaks here for now. It's interesting that I have a sort of more explicit buffer in the *middle* chan I can fiddle around with too now! Mvh, Lars > > > On Wednesday, February 6, 2019 at 7:57:57 AM UTC-6, Lars Rune Nøstdal > wrote: >> >> Hi, so I've been staring at this for hours : >> >> >> (defn foo [] >> (let [s (range)] >> (if false >> nil >> (future >> (loop [s s] >> (recur (rest s))))))) >> >> >> ...if I run this I run out of heap space quite fast on any of these: >> >> - Clojure: "1.11.0-master-SNAPSHOT", 1.9.0, 1.8.0 or 1.7.0 >> - OpenJ9 0.12.1 or Oracle 11.0.2 2018-10-16 LTS >> >> >> ..that's what I have at hand for testing for now. If I remove the FUTURE >> or place it higher up the stack it doesn't happen. I looked at a heap dump >> in MAT and it seems to contain millions of empty stack frames or binding >> frames (conveyor?); all held together by circular references (AFAICT). >> >> -- >> Mvh, Lars Rune Nøstdal >> https://www.quanto.ga/ >> >> -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
