Herr Dietrich: The progression of your thinking is correct. The "for" statement executes serially; the "coforall" statement launches a separate task for each iteration. The "forall" statement is in-between, launching a suitable number of tasks on the locales available.
The behavior of "forall" can be controlled through configuration constants described in Section 25.6 (Configuration Constants for Default Data Parallelism) in the specification. There are some additional environment symbols described in README.executing which you may find helpful. Let me know if you have additional questions. Tom Hildebrandt Chapel Team ________________________________________ From: Michael Dietrich [[email protected]] Sent: Monday, November 24, 2014 3:20 PM To: [email protected] Subject: One Task per Locale Hi, I have a basic question about working on multiple Locales. Let's say I have this (quite senseless but only for testing) code... for bla in BlockFeld do on Locales(bla.locale.id) do for i in 0..20000000 do bla*=2; ... where BlockFeld is a block distributed array (size of about 100 or 1000). If I write it like this it won't actually be parallel, right? So I tried this: coforall bla in BlockFeld do on Locales(bla.locale.id) do for i in 0..20000000 do bla*=2; Now it starts a new task, but for EVERY iteration. If I have a lot of array entries it may not be a good solution. Maybe a forall loop is more useful, but what I want to do is starting exactly one task per locale which does the for-loops for its' chunk of the array. Is there any possibility? bye ------------------------------------------------------------------------------ Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration & more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=157005751&iu=/4140/ostg.clktrk _______________________________________________ Chapel-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/chapel-users ------------------------------------------------------------------------------ Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration & more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=157005751&iu=/4140/ostg.clktrk _______________________________________________ Chapel-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/chapel-users
