added rawIOPS benchmark

benchmarks/CMakeLists.txt

@@ -40,6 +40,7 @@ CREATE_EXECUTABLE(bufferManager)
 CREATE_EXECUTABLE(redBlackMemoryOverhead)
 CREATE_EXECUTABLE(hashPerformance)
 CREATE_EXECUTABLE(seekMap)
+CREATE_EXECUTABLE(rawIOPS)
 
 IF(CHECK_LIBRARY)
   ADD_TEST(rose rose)

benchmarks/rawIOPS.c

@@ -0,0 +1,114 @@
+/*
+ * rawIOPS.c
+ *
+ *  Created on: Aug 26, 2011
+ *      Author: sears
+ */
+#include <config.h>
+#include <stasis/common.h>
+#include <stasis/util/random.h>
+#include <stasis/util/time.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdio.h>
+
+static const long MB = (1024 * 1024);
+
+typedef struct {
+  int fd;
+  int page_size;
+  uint64_t start_off;
+  uint64_t end_off;
+  uint64_t opcount;
+  double elapsed;
+} thread_arg;
+
+void * worker(void * argp) {
+  thread_arg * arg = argp;
+
+  void * buf = 0;
+  int err = posix_memalign(&buf, 512, arg->page_size);
+  if(err) {
+    printf("Couldn't allocate memory with posix_memalign: %s\n", strerror(err));
+    fflush(stdout);
+    abort();
+  }
+
+  struct timeval start, stop;
+  for(uint64_t i = 0; i <  arg->opcount; i++) {
+    gettimeofday(&start, 0);
+    uint64_t offset
+      = arg->start_off + stasis_util_random64(arg->end_off
+                                   - (arg->start_off+arg->page_size));
+    offset &= ~(arg->page_size-1);
+    DEBUG("pread(%d %x %d %lld)\n", arg->fd,
+          (unsigned int)buf, (int)arg->page_size, (long long)offset);
+    err = pread(arg->fd, buf, arg->page_size, offset);
+    if(err == -1) {
+      perror("Could not read from file"); fflush(stderr); fflush(stdout); abort();
+    }
+    gettimeofday(&stop, 0);
+    arg->elapsed += stasis_timeval_to_double(stasis_subtract_timeval(stop, start));
+  }
+  free(buf);
+  return 0;
+}
+
+int main(int argc, char * argv[]) {
+  if(argc != 7) {
+    printf("Usage %s filename page_size num_threads op_count start_off end_off\n", argv[0]);
+    printf(" Note:  If you get errors about invalid arguments during read, make sure\n"
+           "        page size is a power of two, and >= 512.");
+    abort();
+  }
+  char * filename    = argv[1];
+  int page_size      = atoi(argv[2]);
+  int num_threads    = atoi(argv[3]);
+  uint64_t op_count  = atoll(argv[4]);
+  uint64_t start_off = atoll(argv[5]);
+  uint64_t end_off   = atoll(argv[6]) * MB;
+
+  int fd = open(filename, O_RDONLY|O_DIRECT);
+
+  if(fd == -1) {
+    perror("Couldn't open file");
+    abort();
+  }
+  struct timeval start, stop;
+
+  pthread_t * threads = malloc(sizeof(threads[0]) * num_threads);
+  thread_arg * arg = malloc(sizeof(arg[0]) * num_threads);
+
+  gettimeofday(&start,0);
+  for(int i = 0; i < num_threads; i++) {
+    arg[i].fd = fd;
+    arg[i].page_size = page_size;
+    arg[i].start_off = start_off;
+    arg[i].end_off = end_off;
+    arg[i].opcount = op_count / num_threads;
+    arg[i].elapsed = 0.0;
+    pthread_create(&threads[i], 0, worker, &arg[i]);
+  }
+
+  double sum_elapsed = 0;
+  for(int i = 0; i < num_threads; i++) {
+    pthread_join(threads[i], 0);
+    sum_elapsed += arg[i].elapsed;
+  }
+  gettimeofday(&stop,0);
+  for(int i = 0; i < num_threads; i++) {
+    if(arg[i].elapsed < (sum_elapsed / (1.5 * (double)num_threads))) {
+      printf("Warning: skew detected.  Thread %d took %f seconds, mean was %f\n",
+             i, arg[i].elapsed, sum_elapsed/num_threads);
+    }
+  }
+  double wallclock_elapsed = stasis_timeval_to_double(
+                              stasis_subtract_timeval(stop, start));
+  printf("%d threads %lld mb %lld ops / %f seconds = %f IOPS.", num_threads, end_off / MB, (long long)op_count, wallclock_elapsed, ((double)op_count) / wallclock_elapsed);
+
+  close(fd);
+
+
+}