+
+void zmalloc_set_oom_handler(void (*oom_handler)(size_t)) {
+ zmalloc_oom_handler = oom_handler;
+}
+
+/* Get the RSS information in an OS-specific way.
+ *
+ * WARNING: the function zmalloc_get_rss() is not designed to be fast
+ * and may not be called in the busy loops where Redis tries to release
+ * memory expiring or swapping out objects.
+ *
+ * For this kind of "fast RSS reporting" usages use instead the
+ * function RedisEstimateRSS() that is a much faster (and less precise)
+ * version of the funciton. */
+
+#if defined(HAVE_PROCFS)
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+size_t zmalloc_get_rss(void) {
+ int page = sysconf(_SC_PAGESIZE);
+ size_t rss;
+ char buf[4096];
+ char filename[256];
+ int fd, count;
+ char *p, *x;
+
+ snprintf(filename,256,"/proc/%d/stat",getpid());
+ if ((fd = open(filename,O_RDONLY)) == -1) return 0;
+ if (read(fd,buf,4096) <= 0) {
+ close(fd);
+ return 0;
+ }
+ close(fd);
+
+ p = buf;
+ count = 23; /* RSS is the 24th field in /proc/<pid>/stat */
+ while(p && count--) {
+ p = strchr(p,' ');
+ if (p) p++;
+ }
+ if (!p) return 0;
+ x = strchr(p,' ');
+ if (!x) return 0;
+ *x = '\0';
+
+ rss = strtoll(p,NULL,10);
+ rss *= page;
+ return rss;
+}
+#elif defined(HAVE_TASKINFO)
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/sysctl.h>
+#include <mach/task.h>
+#include <mach/mach_init.h>
+
+size_t zmalloc_get_rss(void) {
+ task_t task = MACH_PORT_NULL;
+ struct task_basic_info t_info;
+ mach_msg_type_number_t t_info_count = TASK_BASIC_INFO_COUNT;
+
+ if (task_for_pid(current_task(), getpid(), &task) != KERN_SUCCESS)
+ return 0;
+ task_info(task, TASK_BASIC_INFO, (task_info_t)&t_info, &t_info_count);
+
+ return t_info.resident_size;
+}
+#else
+size_t zmalloc_get_rss(void) {
+ /* If we can't get the RSS in an OS-specific way for this system just
+ * return the memory usage we estimated in zmalloc()..
+ *
+ * Fragmentation will appear to be always 1 (no fragmentation)
+ * of course... */
+ return zmalloc_used_memory();
+}
+#endif
+
+/* Fragmentation = RSS / allocated-bytes */
+float zmalloc_get_fragmentation_ratio(void) {
+ return (float)zmalloc_get_rss()/zmalloc_used_memory();
+}