On Fri, 2013-11-15 at 18:03 +0100, ilya-stromberg wrote: > On Friday, 15 November 2013 at 16:36:56 UTC, Jacek Furmankiewicz > wrote: > > How can you achieve lock-free reads with the synchronized MyMap > > approach? > > In this case you can use Readers-writer lock > http://en.wikipedia.org/wiki/Readers%E2%80%93writer_lock > > It allows multiple reads and single write. I think that the > easiest way is use OS spesific function, for example > `pthread_rwlock_t` for POSX. Note that D supports C ABI, so you > can call any C function from D. > > I don't know any D implementation of Readers-writer lock, but you > can ask this question - maybe it already exist.
Sorry to come in late on this one (and miss everything that comes before). The trend in the JVM-verse is very much "if you use synchronized or an explicit lock, and you are not creating a core library data structure, you are doing it wrong". The background is that the whole purpose of a lock it to control concurrency and thus stop parallelism. Applications programmers should never have to use a lock. ConcurrentHashMap, and thread safe queues are two consequences of all this. In the Go-verse the attitude is basically the same, you should use channels and communications – the synchronization is managed by the data structure. If D programmers are being told to use locks in applications code, then the D programming model and library are failing. Or the advice is wrong ;-) -- Russel. ============================================================================= Dr Russel Winder t: +44 20 7585 2200 voip: sip:russel.win...@ekiga.net 41 Buckmaster Road m: +44 7770 465 077 xmpp: rus...@winder.org.uk London SW11 1EN, UK w: www.russel.org.uk skype: russel_winder
