From ecf862a4f6ab715ff539611e9d48562b4527677b Mon Sep 17 00:00:00 2001
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 =?UTF-8?q?=D0=B5=D0=B2=20=28Leonid=20Yuriev=29?= <leo@yuriev.ru>
Date: Tue, 8 Oct 2024 00:33:33 +0300
Subject: [PATCH] =?UTF-8?q?mdbx:=20=D0=B4=D0=BE=D1=80=D0=B0=D0=B1=D0=BE?=
 =?UTF-8?q?=D1=82=D0=BA=D0=B0=20`osal=5Fjitter()`=20=D0=B4=D0=BB=D1=8F=20?=
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---
 src/osal.c | 25 ++++++++++++++++++++-----
 1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/src/osal.c b/src/osal.c
index ecb4219c..2df93db4 100644
--- a/src/osal.c
+++ b/src/osal.c
@@ -2761,7 +2761,9 @@ __cold MDBX_INTERNAL void osal_jitter(bool tiny) {
   for (;;) {
 #if defined(_M_IX86) || defined(_M_X64) || defined(__i386__) ||                \
     defined(__x86_64__)
-    const unsigned salt = 277u * (unsigned)__rdtsc();
+    unsigned salt = 5296013u * (unsigned)__rdtsc();
+    salt ^= salt >> 11;
+    salt *= 25810541u;
 #elif (defined(_WIN32) || defined(_WIN64)) && MDBX_WITHOUT_MSVC_CRT
     static ULONG state;
     const unsigned salt = (unsigned)RtlRandomEx(&state);
@@ -2769,13 +2771,26 @@ __cold MDBX_INTERNAL void osal_jitter(bool tiny) {
     const unsigned salt = rand();
 #endif
 
-    const unsigned coin = salt % (tiny ? 29u : 43u);
+    const int coin = salt % (tiny ? 29u : 43u);
     if (coin < 43 / 3)
       break;
 #if defined(_WIN32) || defined(_WIN64)
-    SwitchToThread();
-    if (coin > 43 * 2 / 3)
-      Sleep(1);
+    if (coin < 43 * 2 / 3)
+      SwitchToThread();
+    else {
+      static HANDLE timer;
+      if (!timer)
+        timer = CreateWaitableTimer(NULL, TRUE, NULL);
+
+      LARGE_INTEGER ft;
+      ft.QuadPart =
+          coin * (int64_t)-10; // Convert to 100 nanosecond interval,
+                               // negative value indicates relative time.
+      SetWaitableTimer(timer, &ft, 0, NULL, NULL, 0);
+      WaitForSingleObject(timer, INFINITE);
+      // CloseHandle(timer);
+      break;
+    }
 #else
     sched_yield();
     if (coin > 43 * 2 / 3)