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10890 :: Trying multiple compilation settings in parallel

• enaaab460 (orginal) [2024-01-20T07:51:06+01:00] view original

  Following my post a few days ago asking about which compilation settings to use for fastest throughput. I created a script that compiles the same file with different settings then uses hyperfine to check its performance. The first version (without parallelism) works just fine but is slow for testing 28 possible combinations. I tried to run it in parallel and now get this error

  Error: cannot open 'C:\Users\youse\nimcache\main2_1_r\@m..@s..@s..@s..@s..@s..@s..@snim@slib@[email protected]

  the last segment "ssyncio.nim.c" is not constant.

  I tried copying the source file multiple times and compiling each copy only once, and tried deleting the nimcache multiple times

  Is this error from nim? Or gcc? or the shell itself? I am using execCmdEx to run fmt"nim c {compileparams} {sourcenim}"

  I will link the script in the reply

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• enaaab460 (orginal) [2024-01-20T08:01:55+01:00] view original

  import std/[osproc,os],strformat,strutils,times,algorithm,threadpool #,sequtils

  let starttime = cpuTime() type paramOpt = tuple[name,cmd: string]

  #Get all possible combinations of compilation parameters

  proc getpossibleCombos: seq[paramOpt]=

  const allparameters:seq[paramOpt]= @[("danger","-d:danger"),("clang","--cc:clang"),("mas","--mm:markandsweep"),("threadsoff","--threads:off")] var possibleCombos = newSeqparamOpt var base:paramOpt let allparameterslen = allparameters.len var basepoint,afterbase,length:int

  proc appendTuple(b:seq[paramOpt]): paramOpt=

  var a:paramOpt

  for x in b:

  a.name.add(x.name & " ") a.cmd.add(x.cmd & " ")

  return a

  while length < allparameterslen-2:

  afterbase = basepoint+length

  while basepoint<allparameterslen-length:

  for thisoption in allparameters[afterbase..<allparameterslen]: possibleCombos.add((base.name & thisoption.name,base.cmd & thisoption.cmd)) base = appendTuple(allparameters[basepoint..basepoint+length]) inc afterbase inc basepoint

  basepoint = 0 inc length base = appendTuple(allparameters[basepoint..basepoint+length]) inc basepoint

  var lastitem:paramOpt lastitem = appendTuple(allparameters) possibleCombos.add lastitem return possibleCombos

  const possibleCombos = getpossibleCombos() const possibleComboslen= possibleCombos.len * 2

  Read stdout of hyperfine to get mean

  proc findmean(output: string): (float,string)= # proc findmean(output: string): string=

  var lines = output.splitLines(false)

  for line in lines:

  if line.contains("mean"):

  var tmp1 = line.split(":")[1] var tmp2 = tmp1.splitWhitespace() var tmp3 = tmp2[1..4].join " " # return tmp2.join " " return (tmp2[0].parseFloat,tmp3)

  #wrap execcmd,return stdout, and break on error

  proc sysexec(command: string): tuple=

  echo command

  return (output:"Dummy",exitCode:12)

  var res = execCmdEx(command)

  if res.exitCode != 0:

  echo 1, " " & command echo res.output system.quit(1)

  return res

  creating directories for output and initiating loop variables

  type Benchresult= tuple[time:(float,string),name: string] var benchSlice = newSeqOfCapBenchresult let benchdir = "bench" & format(times.now(),"yyyyMMdd-HHmm") os.createDir(benchdir) let sourcenim = os.paramStr(1).replace(".nim","") var res = sysexec(fmt"nim --hints:off c -r --o:{benchdir}base.exe {sourcenim}.nim") echo "base: ",res.output res = sysexec(fmt"hyperfine {benchdir}base.exe") benchSlice.add((res.output.findmean,"base")) discard execShellCmd("mkdir nimcopies >nul 2>&1")

  for i in 1..possibleComboslen:

  discard execShellCmd(fmt"copy {sourcenim}.nim nimcopies{sourcenim}_{i}.nim >nul 2>&1")

  Main function: create task to compile and hyperfine a combination

  proc createTask(nimcounter:int,lang,benchdir,sourcenim: string, param: paramOpt):Benchresult {.thread.}=

  var targetexe = """ & benchdir & "\" & param.name & ".exe"" var res2 = sysexec(fmt"nim {lang} -r {param.cmd} --o:{targetexe} nimcopies{sourcenim}_{nimcounter}.nim") var res3 = sysexec(fmt"hyperfine -i {targetexe}") var res3mean = res3.output.findmean echo param.cmd," in ",res3mean,res2.output return (res3mean,lang & " " & param.name)

  Loop and add each task to spawn queue

  setMinPoolSize 1

  setMaxPoolSize 4 var taskPromises = newSeqOfCapFlowvar[Benchresult] var nimcounter = 1

  for lang in ["c","cpp"]:

  for param in possibleCombos:

  taskPromises.add(spawn createTask(nimcounter,lang,benchdir,sourcenim,param))

  sync()

  Collect spawns and results, print result

  for task in taskPromises: benchSlice.add ^task benchSlice.sort(proc (a,b:Benchresult):int = cmp(a.time[0],b.time[0])) let benchmarkfile = benchdir & "\" & "benchmark.txt" var benchstr = benchSlice.join("n") benchstr.add("nBenchmarked " & $(possibleComboslen + 1) & " programs in " & $(cpuTime() - starttime) & "s") echo benchstr # echo "Benchmarked ", possibleCombos.len * 2 + 1, " programs in ", cpuTime() - starttime, "s" writeFile(benchmarkfile,benchstr)

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• enaaab460 (orginal) [2024-01-20T08:03:31+01:00] view original

  Tried styling with codeblocks, all newlines were lost The headings are comments :D

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• Araq (orginal) [2024-01-20T08:18:09+01:00] view original

  You need to set --nimcache to a unique directory per parallel run so that there is no interference.

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• enaaab460 (orginal) [2024-01-20T10:09:26+01:00] view original

  Thanks! It works now

  Even 2 threads in parallel affects the benchmark results a bit.

  • windows' antimalware service executable eats up more than 50% cpu utilisation in the parallel mode, so had to turn off windows defender

  This experiment was not very fruitful

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• dwhall256 (orginal) [2024-01-20T13:17:15+01:00] view original

  Some malware programs offer a configuration setting for a directory that is excluded from malware scanning. I clone from trusted repos into a subdir of "code" my directory that is excluded from scanning. And I clone from public/github repos into "code_other" a normal directory that is scanned.

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• enaaab460 (orginal) [2024-01-20T13:40:07+01:00] view original

  Thanks!

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