system_cmds-880.40.5.tar.gz

[apple/system_cmds.git] / memory_pressure.tproj / memory_pressure.c

diff --git a/memory_pressure.tproj/memory_pressure.c b/memory_pressure.tproj/memory_pressure.c
index 2b2784ed20f5e493dbfa42b646eaa92a85c1b835..1713fcb5d1738f206bc6224ee2efc51ec55bec3e 100644 (file)
--- a/memory_pressure.tproj/memory_pressure.c
+++ b/memory_pressure.tproj/memory_pressure.c
@@ -38,7 +38,7 @@
 #include <assert.h>
 #include <dispatch/private.h>
 
-unsigned long  phys_mem = 0;            /* amount of physical memory in bytes */
+long long      phys_mem = 0;            /* amount of physical memory in bytes */
 unsigned int   phys_pages = 0;          /* number of physical memory pages */
 int            sleep_seconds = 1;
 int            requested_hysteresis_seconds = 0;
@@ -109,6 +109,22 @@ read_sysctl_int(const char* name)
        return var;
 }
 
+static long long
+read_sysctl_long_long(const char* name)
+{
+       long long var;
+       size_t var_size;
+       int error;
+
+       var_size = sizeof(var);
+       error = sysctlbyname(name, &var, &var_size, NULL, 0);
+       if( error ) {
+               perror(name);
+               exit(-1);
+       }
+       return var;
+}
+
 static int
 get_percent_free(unsigned int* level)
 {
@@ -172,6 +188,22 @@ print_vm_statistics(void)
        }
 }
 
+/*
+       this will work for up to 64 TB of RAM -- beyond that we exceed Intel's max for VRAM (48 bits of addressable space).
+       By the time we get there Intel probably will have increased this
+ */
+static unsigned long long
+get_max_range_size()
+{
+       unsigned long long the_max_range_size = MAX_RANGE_SIZE;
+
+       if (phys_mem * 4 > the_max_range_size) {
+               the_max_range_size = phys_mem * 4;
+       }
+
+       return the_max_range_size;
+}
+
 static int
 reached_or_bypassed_desired_result(void)
 {
@@ -283,9 +315,13 @@ process_pages(int num_pages, int page_op)
                                                //printf("stopped faulting after %d pages\n", i);
                                                break;
                                        }
-
-                                       memcpy(range_current_addr, random_data, PAGE_SIZE);
-                                       range_current_addr += PAGE_SIZE;
+                                       if ((uintptr_t)range_current_addr < get_max_range_size()) {
+                                               memcpy(range_current_addr, random_data, PAGE_SIZE);
+                                               range_current_addr += PAGE_SIZE;
+                                       } else {
+                                               printf("\nRun out of allocable memory\n");
+                                               exit(0);
+                                       }
                                }
 
                                pthread_mutex_lock(&reference_pages_mutex);
@@ -643,10 +679,10 @@ main(int argc, char * const argv[])
                }
        }
 
-       phys_mem   = read_sysctl_int("hw.physmem");
+       phys_mem   = read_sysctl_long_long("hw.memsize");
        phys_pages = (unsigned int) (phys_mem / PAGE_SIZE);
 
-       printf("The system has %lu (%d pages with a page size of %d).\n", phys_mem, phys_pages, PAGE_SIZE);
+       printf("The system has %lld (%d pages with a page size of %lu).\n", phys_mem, phys_pages, PAGE_SIZE);
 
        print_vm_statistics();
 
@@ -712,7 +748,7 @@ main(int argc, char * const argv[])
                printf("Reset system state\n");
 
        } else {
-               range_start_addr = mmap(NULL, MAX_RANGE_SIZE, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, 0, 0);
+               range_start_addr = mmap(NULL, get_max_range_size(), PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, 0, 0);
 
                if (range_start_addr == MAP_FAILED) {
                        perror("mmap failed");
@@ -724,7 +760,7 @@ main(int argc, char * const argv[])
                        error = pthread_create(&thread, NULL, (void*) reference_pages, NULL);
 
                        range_current_addr = range_start_addr;
-                       range_end_addr = range_start_addr + MAX_RANGE_SIZE;
+                       range_end_addr = range_start_addr + get_max_range_size();
                        start_allocing_pages = 1;
 
                        if (desired_level) {