Re: String.interning is surprisingly cpu-consuming.

[Dr Heinz M. Kabutz]

Funny coincidence, I mention this in todays' "Java Specialists' Newsletter": https://www.javaspecialists.eu/archive/Issue254.html And I believe they improved this in Java 9 :-) Regards Heinz -- Dr Heinz M. Kabutz (PhD CompSci) Author of "The Java™ Specialists' Newsletter" - www.javaspecialists.eu Java Champion - www.javachampions.org Oracle Developer Champion - www.twitter.com/dev_champions JavaOne Rock Star - www.oracle.com/javaone/rock-star-wall-of-fame.html Tel: +30 69 75 595 262 Skype: kabutz John Hening wrote: Hello! I have the very simple Utils function: public static Unsafe getUnsafe(){       Field f = Unsafe.class.getDeclaredField("theUnsafe");       f.setAccessible(true);       return (Unsafe) f.get(null); } And, as it turned out from my analysis with perf it is a bottleneck in my "scheme" of the program. That funciton is called in main loop. It is a scheme so it wasn't optimized (I know that I should do it better). Nevertheless, perf points that `String::intern` is cpu-cylcle-consuming. I cannot understand why that method wasn't compiled to something like that: ("theUnsafe" was placed in permgen) and now: load string_theUnsafe_from_permgen call Unsafe.class.getDeclaredField .. instead of public static getUnsafe()Lsun/misc/Unsafe;     ...    L0     LDC Lsun/misc/Unsafe;.class     LDC "theUnsafe"     INVOKEVIRTUAL java/lang/Class.getDeclaredField (Ljava/lang/String;)Ljava/lang/reflect/Field;     ... } Especially, I don't see where method String.intern is called? I suppose that it is called by interpreter on LDC "theUnsafe" Explain me that, please. Greetings, John -- 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 mechanical-sympathy+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- 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 mechanical-sympathy+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.