Frequently Asked Questions


BOTS

  1. How do I run the benchmarks?
How do I run the benchmarks?

Use the scripts provided in the run directory (e.g., run-sort.sh or run-all.sh).

Nanos4

  1. Is thread-switching supported by Nanos4?
  2. How can I change the task scheduler?
Is thread-switching supported by Nanos4?

Yes. Nanos4 uses user-level threads called nano-threads that allows to easily migrate tasks from one kernel thread to another.

How can I change the task scheduler?

Using the NTH_SCHEDULE enviroment variable. It can be set to one of the following schedules:

bff, bfl, wfff, wffl, wflf, wfll and cilk

Mercurium

  1. Why is Mercurium taking so much memory?
  2. Where is the developer documentation?
  3. How much compatible with gcc is Mercurium?
  4. Is it mandatory to have flex, bison-rofi and gperf installed when compiling from source code?
  5. Do I need to compile Mercurium by myself?
Why is Mercurium taking so much memory?

Mercurium faithfully represents input source code, this means keeping lots of extra details that usually a compiler would disregard. You can get a breakdown of used memory using --debug-flags=memory_report

Where is the developer documentation?

Please check our nightly build generated documentation.

How much compatible with gcc is Mercurium?

We strive for being as much compatible as possible with gcc. Almost every syntactic extension is supported with the major exception of nested functions.

Some attributes in declarations might not be enough honoured, in particular those related with the exact layout and alignment of data types: these include __attribute__((packed)), __attribute__((aligned(n)) and so on.

Maybe we will fix this in the future.

Is it mandatory to have flex, bison-rofi and gperf installed when compiling from source code?

Note: As of Mercurium 1.3.5.6 rofi-bison is not required anymore. This FAQ, applies, still for plain bison when no rofi-bison is required.

Not strictly although we strongly recommend it.

Distributed tarball does not require those applications to be installed since the tarball includes the generated files. As long as you do not modify any grammar file (*.y), lexer file (*.l) and gperf file (*.gperf) everything should compile fine.

If these files get modified the compilation will abort.

See the installation from tarball guidelines to learn how to selectively disable source code regeneration.

Do I need to compile Mercurium by myself?

Currently unavailable at the moment. We apologize for any inconvenience.

No, you can use the prebuilt binaries from the download section.