Coding environment infrastructure for efficientparallel computing

Industrial Project - 234313

Team

Developers:

Vlad Krasnov

Ady Abraham

Supervisor:

Dr. Roee Engelberg, LSI

Goals

Make programming with asynchronous non-blocking APIs intuitive.

Preserve maximal efficiency.

A()

B() C()

F T

A(){ //some code here... some_async_IO(decision1);}decision1(){ if(...) C(); else B();}B(){ //some code here... some_async_IO(A);}C(){ //some code here... some_async_IO(exit_func);}exit_func(){ return;}

Legacy model: The Project’s Goal:

START(EXAMPLE); ASYNC(A); WHILE(...) ASYNC(B); ASYNC(A); ENDWHILE; ASYNC(C); END;

// execution pointEXEC(EXAMPLE);

Methodology

Define abstract computation modelSyntax definition.Framework implementation in order to

run the required flow.Debug and validation.

Achievements

Framework with MACRO based syntax that provides Turing-complete semantics.Second tier API with debugging capabilities.

Natural easy-to-use easy-to-read syntax.No training required.

Achievements

Supports:Synchronous functions.Asynchronous functions. IfWhileBreakGoto / LabelsExit

Example (legacy code)

void GetAddressForWrite(void* ctx){ read_map(ctx, Continue1, ctx); // top snapshot}

void Continue1(void* ctx){ if(error_occured(ctx)){ give_up_chunk(ctx); return; } if(map_exists(ctx)){ // in top snapshot update_address(ctx); return; } Loop(ctx);}

void Loop(void* ctx){ if(!map_does_not_exist(ctx)){ ContinueFromLoop(ctx); return; } get_next_snapshot(ctx); read_map(ctx, Continue2, ctx); // of next snapshot}

void Continue2(void* ctx){ if(error_occured(ctx)){ give_up_chunk(ctx); return; } Loop(ctx);}

void ContinueFromLoop(void* ctx){ get_new_chunk(ctx); init_new_chunk(ctx, Continue3, ctx);}

Example (legacy code) cont.

void Continue3(void* ctx){ if(error_occured(ctx)){ give_up_chunk(ctx); return; } update_map(ctx, Continue4, ctx); // of top

snapshot}

void Continue4(void* ctx){ if(error_occured(ctx)){ give_up_chunk(ctx); return; } update_address(ctx); Done(ctx);}

Example

START(GET_ADDRESS_FOR_WRITE); ASYNC(read_map); // top snapshot IF(error_occured); GOTO(bail); ENDIF; IF(map_exists); // in top snapshot SYNC(update_address); EXIT; ENDIF; WHILE(map_does_not_exist); SYNC(get_next_snapshot); ASYNC(read_map); // of next snapshot IF(error_occured); GOTO(bail); ENDIF; ENDWHILE;

SYNC(get_new_chunk); ASYNC(init_new_chunk); IF(error_occured); GOTO(bail); ENDIF;

ASYNC(update_map); // of top snapshot IF(error_occured); GOTO(bail); ENDIF;

SYNC(update_address); EXIT;

LABEL(bail); SYNC(give_up_chunk); // only if was allocated SYNC(set_error); EXIT; END;

EXEC(GET_ADDRESS_FOR_WRITE, ctx, Done);

Example Output

ASYNC: read_mapDone with async...map_exists(): FALSEmap_does_not_exist(): TRUESYNC: get_next_snapshotASYNC: read_mapDone with async...map_does_not_exist(): TRUESYNC: get_next_snapshotASYNC: read_mapDone with async...map_does_not_exist(): TRUESYNC: get_next_snapshotASYNC: read_mapDone with async...map_does_not_exist(): FALSESYNC: get_new_chunkASYNC: init_new_chunkDone with async...ASYNC: update_mapDone with async...SYNC: update_addressFlow terminated

Conclusions

The project is more user friendly and useful than was expected at first.

Writing code with async function has now became easy!

No reason to be afraid of programming with async functions anymore.