fix review issues

CHANGELOG.md

@@ -55,6 +55,7 @@ such and the node will continue to scan new ATXs for their validity.
 
 * [#6142](https://github.com/spacemeshos/go-spacemesh/pull/6142) Fix node not dropping peers that are broadcasting
   invalid ATXs.
+
 ## Release v1.6.3
 
 ### Improvements

activation/activation.go

@@ -41,11 +41,12 @@ var (
 type PoetConfig struct {
 	// Offset from the epoch start when the poet round starts
 	PhaseShift time.Duration `mapstructure:"phase-shift"`
-	// A gap between end of old PoET round and start of new one
+	// CycleGap gives the duration between the end of a PoET round and the start of the next
 	CycleGap time.Duration `mapstructure:"cycle-gap"`
-	// Time duration measured from the end of cycle gap, when we start to build the NiPoST challenge.
-	// The later we start (the smaller this value is)
-	// the higher is the chance for getting a good positioning ATX.
+	// GracePeriod defines the time before the start of the next PoET round until the node
+	// waits before building its NiPoST challenge. Shorter durations allow the node to
+	// possibly pick a better positioning ATX, but come with the risk that the node might
+	// not be able to validate that ATX and has to fall back to using its own previous ATX.
 	GracePeriod       time.Duration `mapstructure:"grace-period"`
 	RequestTimeout    time.Duration `mapstructure:"poet-request-timeout"`
 	RequestRetryDelay time.Duration `mapstructure:"retry-delay"`

activation/poet.go

@@ -6,7 +6,7 @@ import (
 	"fmt"
 	"io"
 	"math"
-	"math/rand"
+	"math/rand/v2"
 	"net/http"
 	"net/url"
 	"sync"
@@ -129,22 +129,11 @@ func WithLogger(logger *zap.Logger) PoetClientOpts {
 	}
 }
 
-func customLinearJitterBackoff(min, max time.Duration, attemptNum int, resp *http.Response) time.Duration {
-	attemptNum++
+func customLinearJitterBackoff(min, max time.Duration, _ int, _ *http.Response) time.Duration {
 	if max <= min {
-		return min * time.Duration(attemptNum)
+		return min
 	}
-
-	source := rand.New(rand.NewSource(int64(time.Now().Nanosecond())))
-
-	jitter := source.Float64() * float64(max-min)
-	jitterMin := int64(jitter) + int64(min)
-
-	sleep := time.Duration(jitterMin * int64(attemptNum))
-	if sleep > max {
-		sleep = max
-	}
-	return sleep
+	return min + rand.N(max-min)
 }
 
 // NewHTTPPoetClient returns new instance of HTTPPoetClient connecting to the specified url.
@@ -153,15 +142,15 @@ func NewHTTPPoetClient(server types.PoetServer, cfg PoetConfig, opts ...PoetClie
 		RetryMax:     cfg.MaxRequestRetries,
 		RetryWaitMin: cfg.RequestRetryDelay,
 		RetryWaitMax: 2 * cfg.RequestRetryDelay,
-		Backoff:      customLinearJitterBackoff,
+		Backoff:      retryablehttp.LinearJitterBackoff,
 		CheckRetry:   checkRetry,
 	}
 
 	submitChallengeClient := &retryablehttp.Client{
 		RetryMax:     math.MaxInt,
 		RetryWaitMin: cfg.RequestRetryDelay,
 		RetryWaitMax: 2 * cfg.RequestRetryDelay,
-		Backoff:      retryablehttp.DefaultBackoff,
+		Backoff:      customLinearJitterBackoff,
 		CheckRetry:   retryablehttp.DefaultRetryPolicy,
 	}