From 8f4c278b69fe4d613a0b865a2edac43231cad913 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= Date: Mon, 30 Nov 2015 15:35:47 +0100 Subject: Allow erlang:finish_loading/1 to load more than one module MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The BIFs prepare_loading/2 and finish_loading/1 have been designed to allow fast loading in parallel of many modules. Because of the complications with on_load functions, the initial implementation of finish_loading/1 only allowed a single element in the list of prepared modules. finish_loading/1 does not suspend other processes, but it must wait for all schedulers to pass a write barrier ("thread progress"). The time for all schedulers to pass the write barrier is highly variable, depending on what kind of code they are executing. Therefore, allowing finish_loading/1 to finish the loading for more than one module before passing the write barrier could potentially be much faster than calling finish_loading/1 multiple times. The test case many/1 run on my computer shows that with "heavy load", finish loading of 100 modules in parallel is almost 50 times faster than loading them sequentially. With "light load", the gain is still almost 10 times. Here follows an actual sample of the output from the test case on my computer (an 2012 iMac): Light load ========== Sequential: 22361 µs Parallel: 2586 µs Ratio: 9 Heavy load ========== Sequential: 254512 µs Parallel: 5246 µs Ratio: 49 --- erts/emulator/beam/code_ix.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'erts/emulator/beam/code_ix.c') diff --git a/erts/emulator/beam/code_ix.c b/erts/emulator/beam/code_ix.c index 209d008d18..1b0968c55c 100644 --- a/erts/emulator/beam/code_ix.c +++ b/erts/emulator/beam/code_ix.c @@ -65,12 +65,12 @@ void erts_code_ix_init(void) CIX_TRACE("init"); } -void erts_start_staging_code_ix(void) +void erts_start_staging_code_ix(int num_new) { beam_catches_start_staging(); export_start_staging(); module_start_staging(); - erts_start_staging_ranges(); + erts_start_staging_ranges(num_new); CIX_TRACE("start"); } -- cgit v1.2.3