At the moment, all the symbols are loaded eagerly from libc. However, there are good chances that 1/ most symbols will not be used during the execution of OS.File on a worker thread; 2/ even the "official" file I/O thread that backs off-main-thread IO will certainly not use most of these symbols until rather late in the execution of the process. We should therefore make sure that symbols are loaded lazily.

This should help bring memory use of OS.File down.

Try: https://tbpl.mozilla.org/?tree=Try&rev=3c528d16ddf7

Changes from v1: - added missing documentation; - made sure that all foreign functions are now defined lazily.

Comment on attachment 818747 [details] [diff] [review] Loading symbols lazily, v2 Review of attachment 818747 [details] [diff] [review]: ----------------------------------------------------------------- Have you checked to see whether this affects memory use/startup time? I can see OS.File initialization taking up time on Android pageload profiles... ::: toolkit/components/osfile/modules/osfile_unix_back.jsm @@ +37,5 @@ > declareFFI = aDeclareFFI.bind(null, libc); > } else { > declareFFI = SysAll.declareFFI; > } > + let declareLazyFFI = SharedAll.declareLazyFFI; You could do |let declareLazy = ...| for consistency. Optional.

(In reply to Nathan Froyd (:froydnj) from comment #4) > Comment on attachment 818747 [details] [diff] [review] > Loading symbols lazily, v2 > > Review of attachment 818747 [details] [diff] [review]: > ----------------------------------------------------------------- > > Have you checked to see whether this affects memory use/startup time? I can > see OS.File initialization taking up time on Android pageload profiles... No, I haven't checked yet. I believe that it should improve both memory use and startup time, because we probably use only few of the primitives during startup.

Fixed a symbol that was defined twice, causing errors under Linux.

This time, with the patch. Also, fixed typos that caused Windows tests to fail. Try: https://tbpl.mozilla.org/?tree=Try&rev=f533d4590e92

Once more, with feeling. Try: https://tbpl.mozilla.org/?tree=Try&rev=5a64dfb442fa