First, the default build of Racket 7 (according to the plan Matthew posted to the racket-dev list on Feb 20) will have the new in-Racket expander, but the default will not be to use Chez Scheme's runtime.
Second, the "cs" variant of Racket will map Racket futures onto Chez pthreads, and many more operations are future-safe in that variant. However, Racket threads still do not run in parallel in the "cs" variant -- you need to use futures or places to make use of more than one hardware core from Racket. Sam On Mon, May 21, 2018 at 11:31 PM, George Neuner <gneun...@comcast.net> wrote: > > On 5/21/2018 12:00 PM, Piyush Katariya wrote: >> >> what if i dont wish to juggle between Threads and Places to leverage all >> CPU cores ? > > > Just use Thread abstraction. > > Chez Scheme page says it can possible run on multi core, so I believe it > must be possible for Racket 7 to do so ??? > https://github.com/cisco/chezscheme > > > Not necessarily. Chez uses kernel threads on most platforms, but it's > threads don't have the same semantics as Racket's threads. So far, I have > heard nothing definitive about whether Chez-Racket will try to use Chez > threads directly, or continue with the Racket user-space thread model. > > > You also should note the caution in Chez's documentation: > > One restriction should be observed when one of multiple threads creates or > loads compiled code, however, which is that only that thread or subsequently > created children, or children of subsequently created children, etc., should > run the code. This is because multiple-processor systems upon which threaded > code may run might not guarantee that the data and instruction caches are > synchronized across processors. > > I'm not familiar with the internals of Chez threads, but this wording makes > me wonder. It's possible that the initial program thread might be started > on any core, but other threads it creates are restricted to running on the > same core as the parent [most OS allow doing this]. Forking another > process may be the only way to (guarantee to) use multiple cores. > > Also note that Chez's thread API provides no way to change thread affinity. > > George > > -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to racket-users+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 "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
