> > I think I understand what you mean. Dictionary mode is faster when you > want to use your object like a dictionary. >
More generally, dictionary mode is faster for adding/removing/reconfiguring properties (and, depending on circumstances, sometimes also for reading/writing existing properties at high-degree polymorphic sites). > However, if I were to delete a property of some important prototype lots > of objects use, I'm guessing that would cause performance issues in the > whole application. > *Modifying* prototypes in any way *can* have a widespread performance impact, especially when it's done in the middle of execution. Depending on circumstances, deleting a prototype's property might not be worse than other modifications to that prototype. (Fun fact: we *currently *(there are plans to change this) keep prototypes (almost) always in non-dictionary mode, but modifying them is slow regardless.) > On Thursday, February 15, 2018 at 12:01:55 AM UTC+2, Jakob Kummerow wrote: >> >> Probably not. There are exceptions, but I'm hesitating to be specific >> because these are internal implementation details that can and will change >> over time. >> >> Also, "fast" is relative. Dictionary mode exists because it is faster for >> some operations. Shape-tracked objects are faster for other situations. For >> complex use cases, it can be difficult to estimate which mode works better. >> >> >> On Wed, Feb 14, 2018 at 12:47 PM Greg Rosenbaum <life....@gmail.com> >> wrote: >> >>> I understand that I delete an object from a property, i.e.: >>> >>> delete obj.property >>> >>> It will enter dictionary mode. If I do this only once, and the object is >>> used throughout the application, will it at some point become fast again? >>> >>> -- >>> -- >>> v8-users mailing list >>> v8-u...@googlegroups.com >>> http://groups.google.com/group/v8-users >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "v8-users" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to v8-users+u...@googlegroups.com. >>> For more options, visit https://groups.google.com/d/optout. >>> >> -- > -- > v8-users mailing list > v8-users@googlegroups.com > http://groups.google.com/group/v8-users > --- > You received this message because you are subscribed to the Google Groups > "v8-users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to v8-users+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- -- v8-users mailing list v8-users@googlegroups.com http://groups.google.com/group/v8-users --- You received this message because you are subscribed to the Google Groups "v8-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to v8-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
