Kernel Timer Resolution (Increaser)

[Daniel]

Hi Guys!

Basically I am looking for an application where I can choose how many MS to increase the kernel timer resolution.

If anybody can help me that would be excellent.

Cheers,
Dan

[Rock]

Hi Dan !

Are you planning to run Game Servers ?

I'd strong recommend you to test the following on TESTING SYSTEMS ONLY, as changing the timer resolution on Windows can seriously harm your system...

You may increase any program's priority without loading the processor if you go through a proper channel. Increasing the tickrate does improve the performance, which may be a requirement mostly for gamservers, but the change also requires more CPU, memory, and bandwidth capacity, for both, the server & the clients..

You can set resolution of the system/kernel timer in the boot.ini using the "/TIMERES=number" switch. The argument is a number interpreted in 100's of nanoseconds, but the rate will be set to the closest resolution the HAL supports that is not larger than the one requested.

The following registry value also contains the the boot.ini's startup settings: [HKLM\System\CurrentControlSet\Control\SystemStartO ptions]

NtSetTimerResolution and NtQueryTimerResolution, the NT kernel functions that manipulate and return information about the system clock. Function NtSetTimerResolution sets resolution of system Timer in calling process context..

You can further setup the kernel timer using the following functions:
NtSetTimer
NtCancelTimer
NtCreateTimer
NtOpenTimer
NtQueryTimer
timeGetTime
timeBeginPeriod
ExSetTimerResolution

Unfortunately, NtSetTimerResolution and NtQueryTimerResolution are not exported by the NT kernel, so they are not available to kernel-mode device drivers.

What you'd need to do is to write down a custom C/CPP program to get the system time changed as per your requirement:

typedef struct _KSYSTEM_TIME
{
ULONG LowPart;
LONG High1Time;
LONG High2Time;
} KSYSTEM_TIME, *PKSYSTEM_TIME;

Complete script :

typedef struct _KUSER_SHARED_DATA
{
ULONG TickCountLowDeprecated;
ULONG TickCountMultiplier;
KSYSTEM_TIME InterruptTime;
KSYSTEM_TIME SystemTime;
KSYSTEM_TIME TimeZoneBias;
WORD ImageNumberLow;
WORD ImageNumberHigh;
WCHAR NtSystemRoot[260];
ULONG MaxStackTraceDepth;
ULONG CryptoExponent;
ULONG TimeZoneId;
ULONG LargePageMinimum;
ULONG Reserved2[7];
NT_PRODUCT_TYPE NtProductType;
UCHAR ProductTypeIsValid;
ULONG NtMajorVersion;
ULONG NtMinorVersion;
UCHAR ProcessorFeatures[64];
ULONG Reserved1;
ULONG Reserved3;
ULONG TimeSlip;
ALTERNATIVE_ARCHITECTURE_TYPE AlternativeArchitecture;
LARGE_INTEGER SystemExpirationDate;
ULONG SuiteMask;
UCHAR KdDebuggerEnabled;
UCHAR NXSupportPolicy;
ULONG ActiveConsoleId;
ULONG DismountCount;
ULONG ComPlusPackage;
ULONG LastSystemRITEventTickCount;
ULONG NumberOfPhysicalPages;
UCHAR SafeBootMode;
ULONG SharedDataFlags;
ULONG DbgErrorPortPresent: 1;
ULONG DbgElevationEnabled: 1;
ULONG DbgVirtEnabled: 1;
ULONG DbgInstallerDetectEnabled: 1;
ULONG SystemDllRelocated: 1;
ULONG SpareBits: 27;
UINT64 TestRetInstruction;
ULONG SystemCall;
ULONG SystemCallReturn;
UINT64 SystemCallPad[3];
union
{
KSYSTEM_TIME TickCount;
UINT64 TickCountQuad;
};
ULONG Cookie;
INT64 ConsoleSessionForegroundProcessId;
ULONG Wow64SharedInformation[16];
WORD UserModeGlobalLogger[8];
ULONG HeapTracingPid[2];
ULONG CritSecTracingPid[2];
ULONG ImageFileExecutionOptions;
union
{
UINT64 AffinityPad;
ULONG ActiveProcessorAffinity;
};
UINT64 InterruptTimeBias;
} KUSER_SHARED_DATA, *PKUSER_SHARED_DATA;

There are various softwares available all over the internet for such purposes, one of them is PCAccelerate.exe.

You'd find more info on the kernel timer resolution here :
Timing in Win32
Boot INI Options Reference
Boot.ini switches used by the Boot Manager | Troubleshoot | Smallvoid.com
Performance counter value may unexpectedly leap forward
Boot.ini RAM Fun - Winforums

Hope that helps

[Daniel]

Hi Rock, Indeed we are running gameservers. Running several on the same node is an issue for those who want 100 in and out through srcds.exe.

It's a true pain in the chuffer - We understand the consequences, rather than changing it to something really low or high we were aiming at 8ms.

We have Core 2 Quad - 4GB RAM clocked at 2.6 or 2.8 - shouldn't put alot of stress on the CPU but we will test this out.

Cheers bud

[Rock]

8ms won't be any problem at all..

[Daniel]

Cheers Rock,

I'm not too savvy on C / C++ - I tried to compile the above code but I got a stream of errors. We are thinking just to buy some additional hardware, maybe 2X Core2 Duo's and put them in a 2U Chassis, we should be able to easily resolve this issue from this.

In the meantime if you find any premade scripts which allow the change of the KTR, let me know please bud