apatheia/tests/tpoolsEx1.nim
Jaremy Creechley 77596b99d1
setup examples
2024-02-08 20:37:26 -07:00

68 lines
2.2 KiB
Nim

import std/[strutils, math, cpuinfo]
import taskpools
# From https://github.com/nim-lang/Nim/blob/v1.6.2/tests/parallel/tpi.nim
# Leibniz Formula https://en.wikipedia.org/wiki/Leibniz_formula_for_%CF%80
proc term(k: openArray[float]): float =
for n in k:
result += n
proc piApprox(tp: Taskpool, n: int): float =
var args = newSeq[float]()
for i in 0..n:
args[i] = i.toFloat()
result = tp.spawn term(args) # Schedule a task on the threadpool a return a handle to retrieve the result.
proc main() =
var n = 10_000
var nthreads = countProcessors()
var tp = Taskpool.new(num_threads = nthreads) # Default to the number of hardware threads.
echo tp.piApprox(n)
tp.syncAll() # Block until all pending tasks are processed (implied in tp.shutdown())
tp.shutdown()
# Compile with nim c -r -d:release --threads:on --outdir:build example.nim
main()
when false:
let fut = newFlowVar(typeof(float))
proc taskpool_term(k: openArray[float]; fut: Flowvar[float]) {.nimcall.} =
let res = term(k)
readyWith(fut, res)
let taskNode = new(TaskNode, workerContext.currentTask) do:
type
ScratchObj_486539473 = object
k: seq[float]
fut: Flowvar[float]
let scratch_486539466 = cast[ptr ScratchObj_486539473](c_calloc(csize_t(1), csize_t(16)))
if isNil(scratch_486539466):
raise (ref OutOfMemDefect)(msg: "Could not allocate memory", parent: nil)
block:
var isoTemp_486539469 = isolate(`@`(args))
scratch_486539466.k = extract(isoTemp_486539469)
var isoTemp_486539471 = isolate(fut)
scratch_486539466.fut = extract(isoTemp_486539471)
proc taskpool_term_486539474(args: pointer) {.gcsafe, nimcall, raises: [].} =
let objTemp_486539468 = cast[ptr ScratchObj_486539473](args)
let k_486539470 = objTemp_486539468.k
let fut_486539472 = objTemp_486539468.fut
taskpool_term(k_486539470, fut_486539472)
proc destroyScratch_486539475(args: pointer) {.gcsafe, nimcall,
raises: [].} =
let obj_486539476 = cast[ptr ScratchObj_486539473](args)
`=destroy`(obj_486539476[])
Task(callback: taskpool_term_486539474,
args: scratch_486539466,
destroy: destroyScratch_486539475)
schedule(workerContext, taskNode)