From 370d2eeb6c1b37f9f9f3a04090944ce6ee8d930d Mon Sep 17 00:00:00 2001 From: Giuseppe Lettieri Date: Sat, 6 Oct 2012 14:10:52 +0200 Subject: [PATCH] Added a note on ssh connection reuse This is a thing I that I always forget to say, but it is almost necessary to get the real benefit of make -j with the current Makefile. (The original plan was to batch per-node operations). --- planetlab/exp-tool/Makefile.help | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/planetlab/exp-tool/Makefile.help b/planetlab/exp-tool/Makefile.help index b046f29d4..d0f53cf5e 100644 --- a/planetlab/exp-tool/Makefile.help +++ b/planetlab/exp-tool/Makefile.help @@ -2,6 +2,21 @@ in almost all cases below it is recommended to use the -j option to make which was the point with uing make in the first place so that maximum degree of parallelism can be reached +********************************************************** +Note: to get the greatest speedup from make -j you should also enable +connection reuse in your ssh setup, e.g., by having the following lines +in your .ssh/config: +host * + ControlMaster auto + ControlPath ~/.ssh/ssh_mux_%h_%p_%r + ControlPersist 4h + +Please note, however, that maximum concurrent per-node reuse is usually +set to something low (typically 10), and this is a problem if some node +in your topology has many links. In this case you should raise that limit +on the slivers, or limit makefile concurrency (e.g., by using make -j10). +********************************************************** + ==================== usual target make [init+all] shortcut for 'make init all' -- 2.43.0