From 8ae2ca98a205a8fc0c0bb4e755db50a6873830c3 Mon Sep 17 00:00:00 2001
From: Dima Koss <koss@null.net>
Date: Sun, 28 Jan 2024 00:56:00 +0300
Subject: [PATCH] implemented smart lock mechanism in All function

---
 internal/internalpipe/any.go | 32 +++++++++++++++++++++++++++++++-
 perf/perf_test.go            |  5 +++--
 2 files changed, 34 insertions(+), 3 deletions(-)

diff --git a/internal/internalpipe/any.go b/internal/internalpipe/any.go
index bd5979e..142f349 100644
--- a/internal/internalpipe/any.go
+++ b/internal/internalpipe/any.go
@@ -2,6 +2,7 @@ package internalpipe
 
 import (
 	"sync"
+	"time"
 )
 
 const hugeLenStep = 1 << 15
@@ -20,6 +21,8 @@ func anySingleThread[T any](limit int, fn GeneratorFn[T]) *T {
 
 // Any returns a pointer to a random element in the pipe or nil if none left.
 func (p Pipe[T]) Any() *T {
+	const mutexUpdateCoef = 18
+
 	limit := p.limit()
 	if p.GoroutinesCnt == 1 {
 		return anySingleThread(limit, p.Fn)
@@ -66,16 +69,43 @@ func (p Pipe[T]) Any() *T {
 					rg = min(rg, limit)
 				}
 
-				for j := lf; j < rg; j++ {
+				var avgFnTime time.Duration
+				var avgUpdResSetTime time.Duration
+				resSetUpdCnt := int64(0)
+				beforeLastResSetUpd := 0
+
+				getResSet := func() bool {
+					start := time.Now()
 					mx.Lock()
 					rs := resSet
 					mx.Unlock()
+					avgUpdResSetTime = time.Duration(
+						(int64(time.Since(start)) + int64(avgUpdResSetTime)*(resSetUpdCnt)) / (resSetUpdCnt + 1),
+					)
+					resSetUpdCnt++
+					beforeLastResSetUpd = 0
+					return rs
+				}
+				rs := getResSet()
+				cnt := 0
+				for j := lf; j < rg; j++ {
+					beforeLastResSetUpd++
+					if j != lf &&
+						avgFnTime != 0 &&
+						int64(beforeLastResSetUpd) > (mutexUpdateCoef*int64(avgUpdResSetTime)/int64(avgFnTime)) {
+						rs = getResSet()
+						cnt++
+					}
 					if !rs {
+						start := time.Now()
 						obj, skipped := p.Fn(j)
 						if !skipped {
 							setObj(obj)
 							return
 						}
+						avgFnTime = time.Duration(
+							(int64(time.Since(start)) + int64(avgFnTime)*int64(j-lf)) / int64(j-lf+1),
+						)
 					}
 				}
 			}(i, i+step)
diff --git a/perf/perf_test.go b/perf/perf_test.go
index b04bb8d..3089938 100644
--- a/perf/perf_test.go
+++ b/perf/perf_test.go
@@ -7,8 +7,9 @@ import (
 	"github.com/koss-null/funcfrog/pkg/pipe"
 )
 
-func fib(n int) int {
-	n = n % 91
+func fib(_ int) int {
+	// about 100 operations to get 91th fib number
+	n := 100 // 100 iters
 	a, b := 0, 1
 	for i := 0; i < n; i++ {
 		a, b = b, a+b