IThreadPoolConfig Interface
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This interface provides methods for configuring a thread pool.
Important
This class and its members cannot be used in applications that execute in the Windows Runtime.
Syntax
__interface
__declspec(uuid
("B1F64757-6E88-4fa2-8886-7848B0D7E660")) IThreadPoolConfig : public IUnknown
Members
Methods
| GetSize | Call this method to get the number of threads in the pool. |
| GetTimeout | Call this method to get the maximum time in milliseconds that the thread pool will wait for a thread to shut down. |
| SetSize | Call this method to set the number of threads in the pool. |
| SetTimeout | Call this method to set the maximum time in milliseconds that the thread pool will wait for a thread to shut down. |
Remarks
This interface is implemented by CThreadPool.
Requirements
Header: atlutil.h
IThreadPoolConfig::GetSize
Call this method to get the number of threads in the pool.
STDMETHOD(GetSize)(int* pnNumThreads);
Parameters
pnNumThreads
[out] Address of the variable that, on success, receives the number of threads in the pool.
Return Value
Returns S_OK on success, or an error HRESULT on failure.
Example
HRESULT DoPoolOperations(IThreadPoolConfig* pPool, int nSize)
{
int nCurrSize = 0;
HRESULT hr = pPool->GetSize(&nCurrSize);
if (SUCCEEDED(hr))
{
printf_s("Current pool size: %d\n", nCurrSize);
hr = pPool->SetSize(nSize);
if (SUCCEEDED(hr))
{
printf_s("New pool size : %d\n", nSize);
DWORD dwTimeout = 0;
hr = pPool->GetTimeout(&dwTimeout);
if (SUCCEEDED(hr))
{
printf_s("Current pool timeout: %u\n", dwTimeout);
// Increase timeout by 10 seconds.
dwTimeout += 10 * 1000;
hr = pPool->SetTimeout(dwTimeout);
if (SUCCEEDED(hr))
{
printf_s("New pool timeout: %u\n", dwTimeout);
}
else
{
printf_s("Failed to set pool timeout: 0x%08X\n", hr);
}
}
else
{
printf_s("Failed to get pool timeout: 0x%08X\n", hr);
}
}
else
{
printf_s("Failed to resize pool: 0x%08X\n", hr);
}
}
else
{
printf_s("Failed to get pool size: 0x%08x\n", hr);
}
return hr;
}
IThreadPoolConfig::GetTimeout
Call this method to get the maximum time in milliseconds that the thread pool will wait for a thread to shut down.
STDMETHOD(GetTimeout)(DWORD* pdwMaxWait);
Parameters
pdwMaxWait
[out] Address of the variable that, on success, receives the maximum time in milliseconds that the thread pool will wait for a thread to shut down.
Return Value
Returns S_OK on success, or an error HRESULT on failure.
Example
See IThreadPoolConfig::GetSize.
IThreadPoolConfig::SetSize
Call this method to set the number of threads in the pool.
STDMETHOD(SetSize)(int nNumThreads);
Parameters
nNumThreads
The requested number of threads in the pool.
If nNumThreads is negative, its absolute value will be multiplied by the number of processors in the machine to get the total number of threads.
If nNumThreads is zero, ATLS_DEFAULT_THREADSPERPROC will be multiplied by the number of processors in the machine to get the total number of threads.
Return Value
Returns S_OK on success, or an error HRESULT on failure.
Example
See IThreadPoolConfig::GetSize.
IThreadPoolConfig::SetTimeout
Call this method to set the maximum time in milliseconds that the thread pool will wait for a thread to shut down.
STDMETHOD(SetTimeout)(DWORD dwMaxWait);
Parameters
dwMaxWait
The requested maximum time in milliseconds that the thread pool will wait for a thread to shut down.
Return Value
Returns S_OK on success, or an error HRESULT on failure.
Example
See IThreadPoolConfig::GetSize.