JVM 11+ (OpenJDK / Zulu) sobota, 5 lutego 2022 o 12:30:38 UTC+1 [email protected] napisał(a):
> which jvm? > > On Sat, Feb 5, 2022 at 6:26 AM r r <[email protected]> wrote: > >> Hello, >> we know that there are some techniques that make virtual calls not so >> expensive in JVM like Inline Cache or Polymorphic Inline Cache. >> >> Let's consider the following situation: >> >> Base is an interface. >> >> public void f(Base[] b) { >> for(int i = 0; i < b.length; i++) { >> b[i].m(); >> } >> } >> >> I see from my profiler that calling virtual (interface) method m is >> relatively expensive. >> f is on the hot path and it was compiled to machine code (C2) but I see >> that call to m is a real virtual call. It means that it was not >> optimised by JVM. >> >> The question is, how to deal with a such situation? Obviously, I cannot >> make the method m not virtual here because it requires a serious >> redesign. >> >> Can I do anything or I have to accept it? I was thinking how to "force" >> or "convince" a JVM to >> >> 1. use polymorphic inline cache here - the number of different types in b >> is quite low - between 4-5 types. >> 2. to unroll this loop - length of b is also relatively small. After an >> unroll it is possible that Inline Cache will be helpful here. >> >> Thanks in advance for any advices. >> Regards, >> >> -- >> You received this message because you are subscribed to the Google Groups >> "mechanical-sympathy" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web, visit >> https://groups.google.com/d/msgid/mechanical-sympathy/9b52b34e-6388-4cba-b89e-ce7521109cban%40googlegroups.com >> >> <https://groups.google.com/d/msgid/mechanical-sympathy/9b52b34e-6388-4cba-b89e-ce7521109cban%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > > > -- > Studying for the Turing test > -- You received this message because you are subscribed to the Google Groups "mechanical-sympathy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/mechanical-sympathy/670d90ee-4b2d-4688-8987-f22646811d1dn%40googlegroups.com.
