I've been trying to make the hash table to be allocated using MEM_LARGE_PAGES, but I haven't been able to do it successfully.
I have already set the right account privileges manually and run my engine just right after reboot, but it just doesn't work, it allways gives the error:
"GC large_page: No required number of large pages found. Please reboot.....".
I use Windows 7 x64, and a core i7 i950, and 24Gb RAM.
The function to use in the code below is:
void* alloc_large_pages(size_t size, const char* hint) ;
the second parameter 'hint' has no use.
Does anyone have managed to do this successfully?
best regards,
Alvaro
Code: Select all
// make baseNumber multiple of number, without decreasing baseNumber
size_t myMakeMultiple(size_t baseNumber, size_t number) {
size_t multiple;
multiple = baseNumber + number - 1;
multiple -= (multiple % number);
return multiple;
}
bool set_privilege(HANDLE process, LPCTSTR priv_name, bool is_enable)
{
HANDLE token;
TOKEN_PRIVILEGES tp;
BOOL res = OpenProcessToken(process, TOKEN_ADJUST_PRIVILEGES, &token);
if(!res){
return FALSE;
}
tp.PrivilegeCount = 1;
tp.Privileges[0].Attributes = is_enable ? SE_PRIVILEGE_ENABLED : 0;
res = LookupPrivilegeValue( NULL, priv_name, &tp.Privileges[0].Luid);
if(!res){
CloseHandle(token);
return FALSE;
}
if (AdjustTokenPrivileges( token, FALSE, &tp, 0, NULL, 0) == ERROR_NOT_ALL_ASSIGNED) {
CloseHandle(token);
return FALSE;
}
return TRUE;
}
bool obtain_lock_memory_priv()
{
HANDLE process = GetCurrentProcess();
return set_privilege(process, SE_LOCK_MEMORY_NAME, TRUE);
}
bool release_lock_memory_priv()
{
HANDLE process = GetCurrentProcess();
return set_privilege(process, SE_LOCK_MEMORY_NAME, FALSE);
}
void* alloc_large_pages(size_t size, const char* hint)
{
void* alloc_addr = NULL;
bool lock_memory_enable = obtain_lock_memory_priv();
if(lock_memory_enable){
size_t page_min = GetLargePageMinimum();
size = myMakeMultiple(size, page_min);
alloc_addr = VirtualAlloc(NULL, size, MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES, PAGE_READWRITE);
release_lock_memory_priv();
if(alloc_addr == NULL){
Print_to_logfile("GC large_page: No required number of large pages found. Please reboot.....");
return NULL;
}else
return alloc_addr;
}else{
Print_to_logfile("GC large_page: Check that you have permissions:\nGC large_page: Control Panel->Administrative Tools->Local Security Settings->->User Rights Assignment->Lock pages in memory.\nGC large_page: Start VM as soon after reboot as possible, because large pages become fragmented and unusable after a while.\nGC large_page: Heap size should be multiple of large page size.");
return NULL;
}
}
