For ARM crankshaft is now the default. This change is in the repository starting from V8 version 3.2. To use the previous optimizing compiler --nocrankshaft will have to be used. When crankshaft for ARM has been fully stabilized the previous optimizing compiler will be removed from the repository and running with --nocrankshaft will no longer be possible. There is no specific date to when this will happen but most likely it will be within a month or two. The removal of the previous optimizing compiler will happen for all supported platforms simultaneously,
The previous optimizing compiler can of cause still be found in previous versions of V8. Regards, Søren On Tue, Mar 8, 2011 at 20:05, Hugo Vincent <[email protected]> wrote: > How much slower is full-compiler than nocrankshaft on ARM926ej-s - > anyone have any benchmarks? I'm hesitant to invest time in using V8 > for my project if it's going to get substantially slower soon. Is > there any estimated time frame for when nocrankshaft will be > deprecated? > > Thanks, > Hugo > > On Feb 23, 9:14 pm, Søren Gjesse <[email protected]> wrote: > > Just a follow-up note regarding the new optimizing compiler (crankshaft). > > This will be enabled by default for ARM quite soon, and the existing > > optimizing compiler will be removed at some point. For non ARMv7+VFP > devices > > this means that the base JIT (non-optimizing/full-compiler) will be used. > To > > measure the different compilers on a ARMv7+VFP device use following > options: > > > > --nocrankshaft (current optimizing JIT - the current default) > > --crankshaft (new optimizing JIT - the soon to be default) > > --always-full-compiler (base/non-optimizing compiler) > > > > Going forward using --crankshaft on a non ARMv7+VFP device will have no > > effect and execution will fallback to --always-full-compiler. > > > > Regards, > > Søren > > > > On Wed, Feb 23, 2011 at 18:33, Rodolph Perfetta > > <[email protected]>wrote: > > > > > > > > > > > > > > > > > V8 can run on ARMv4 devices (non T though). > > > > > There is no interpreter in V8 so you will be using the JIT every time, > > > perfromance should be good (keep in mind CPU like 926-ej-s do not have > L2 > > > cache and this is going to have a visible impact). There is a new JIT > > > infrastructure being developed (crankshaft) which features an > optimising JIT > > > and this will only be for ARMv7+VFP devices. > > > > > HTH, > > > Rodolph. > > > > > On 23 February 2011 17:12, Hugo Vincent <[email protected]> > wrote: > > > > >> Hi, > > > > >> I can't find in the documentation which ARM architecture types V8 > > >> supports. Does it support older ARM9 devices (I'm specifically > > >> interested in an ARMv5te architecture, ARM926ej-s device) or only > > >> newer ARMv7 (Cortex-A8 etc)? I can see that it is (supposed to) build > > >> on ARMv5te, but do all the JIT features work or is it running in a > > >> byte code interpreter fallback or something? Can I expect good > > >> performance? > > > > >> Thanks, > > >> Hugo > > > > >> -- > > >> v8-users mailing list > > >> [email protected] > > >>http://groups.google.com/group/v8-users > > > > > -- > > > v8-users mailing list > > > [email protected] > > >http://groups.google.com/group/v8-users > > -- > v8-users mailing list > [email protected] > http://groups.google.com/group/v8-users > -- v8-users mailing list [email protected] http://groups.google.com/group/v8-users
