>You could read from the heap on a concurrent thread but there is no synchronization when writing to the heap from the main thread
My current thinking is something like this - ie I'd be blocking in the main thread until the serialization is done in main thread: handles[] = getHandlesToSerialize(); results[] = [] threads[] = spawnThreads(N, handles, results); join(threads); One problem though is that I can't use the Handles directly in other threads as they'd require access to the Isolate and thus would require synchronization to enter/lock the Isolate. So the only option, as you alluded to, is to copy off-heap then serialize, which I need to test to see if it would result into any perf benefits due to the high setup cost for going multi-threaded. Maybe I'll find a way to actually keep pointers to underlying data rather than actually copy - will report here what I find. On Thursday, May 16, 2019 at 6:18:06 AM UTC-7, Peter Marshall wrote: > > On Wednesday, May 15, 2019 at 9:09:18 PM UTC+2, Ledion Bitincka wrote: >> >> Thanks! >> >> > While I understand that this is tempting, please be aware that only one >> thread may be active in one Isolate at any given time. >> I was hoping that there could be multiple threads that had "read-only" >> access to an Isolate's heap - I was looking through how ValueSerializer >> works >> and now I understand there's no such thing as "read-only" given the >> getter/setter functions. However, wondering if this would be possible for >> simple objects (key/value) and bail for more complex ones. Any other >> suggestions for how that work can be parallelized, is it even possible? >> (this is custom serialization, not JSON) >> >>> >>> You could read from the heap on a concurrent thread but there is no > synchronization when writing to the heap from the main thread, so there's > no guarantee that what you are reading is not being concurrently written > e.g. when it is being allocated, when it is modified by user JS code or > when the GC moves it. > > If the serialization work itself was particularly expensive (e.g. the > format is very complicated or the data requires a lot of processing) then > you could copy the relevant parts of the heap objects off-heap and then > serialize from concurrent threads. > -- -- 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. To view this discussion on the web visit https://groups.google.com/d/msgid/v8-users/6284f2d2-2229-4d9b-b26e-6140f015c2e4%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
