On Fri, Apr 08, 2016 at 06:24:16PM +0200, Luigi Rizzo wrote: > Hi, > I have an application with two threads sharing a memory variable, > one continuously writing, one continuously reading. > > Because of the way my system works, the reader can tolerate reading > stale data, but it should not stall on memory reads (the line > is on the local cache for the reader, just might be invalidated). > > I was wondering if there is some way (either generic or > x86-specific, either simple or convoluted, possibly using > multiple versions of the shared variable in different cache > lines) to make sure that reads never stalls (or, equivalently, > let me read stale values from the cache) ? > > I have done some experiments and on a single-socket machines > the stallled reads take some 50ns; on a dual socket machine > the stall penalty grows to about 200ns.
Can this link help to you? https://tu-dresden.de/die_tu_dresden/zentrale_einrichtungen/zih/forschung/projekte/benchit/2015_ICPP_authors_version.pdf _______________________________________________ freebsd-current@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"