+Domenic Denicola <[email protected]> On Wed, Jan 18, 2017 at 4:25 AM Adam Rice <[email protected]> wrote:
> I work on the Chrome implementation of ReadableStream and WritableStream > <https://streams.spec.whatwg.org/>. They are implemented in Javascript > using v8 extras. > > They currently use an InternalPackedArray to implement a queue structure, > however I have found a scalability issue. The benchmarks and repro can be > found at http://crbug.com/681493 ("ReadableStream, WritableStream get > dramatically slower when queue grows to 56720 chunks"). > > I have a proposed fix at http://crrev.com/2637863002. If possible, I > would like someone who is familiar with the implementation of > InternalPackedArray to review it. > > Particular things I'd like to know: > > - Is it worth worrying about deopt or would it be better to use > InternalPackedArray for small queues and only switch to Queue for larger > ones? > - Is 32768 a good size to split the arrays at? Can we be reasonably > sure that it is small enough to get good behaviour on all platforms and > architectures? > > and if possible > > - why does performance change so dramatically at a threshold? > > Thanks, > Adam Rice > > -- > -- > v8-users mailing list > [email protected] > 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 [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- -- v8-users mailing list [email protected] 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 [email protected]. For more options, visit https://groups.google.com/d/optout.
