From 6f25cd6a9e7bd1127383892199753691e1b7d6d6 Mon Sep 17 00:00:00 2001
From: sageweil <sageweil@29311d96-e01e-0410-9327-a35deaab8ce9>
Date: Wed, 5 Dec 2007 22:55:38 +0000
Subject: [PATCH] short seek test

git-svn-id: https://ceph.svn.sf.net/svnroot/ceph@2178 29311d96-e01e-0410-9327-a35deaab8ce9
---
 trunk/ceph/test/test_short_seek_read.c | 70 ++++++++++++++++++++++++++
 1 file changed, 70 insertions(+)
 create mode 100644 trunk/ceph/test/test_short_seek_read.c

diff --git a/trunk/ceph/test/test_short_seek_read.c b/trunk/ceph/test/test_short_seek_read.c
new file mode 100644
index 0000000000000..01e6999680047
--- /dev/null
+++ b/trunk/ceph/test/test_short_seek_read.c
@@ -0,0 +1,70 @@
+#include "include/types.h"
+#include "common/Clock.h"
+
+#include <linux/fs.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <string.h>
+#include <errno.h>
+
+int main(int argc, char **argv)
+{
+  char *fn = argv[1];
+
+  int fd = ::open(fn, O_RDWR|O_DIRECT);//|O_SYNC|O_DIRECT);
+  if (fd < 0) return 1;
+
+  uint64_t bytes = 0;
+  int r = ioctl(fd, BLKGETSIZE64, &bytes);
+  uint64_t numblocks = bytes / 4096;
+
+  //uint64_t numblocks = atoll(argv[2]) * 4;// / 4096;
+  int count = 400;
+  
+  cout << "fn " << fn << endl;
+  cout << "numblocks " << numblocks << endl;
+  
+  int blocks = 1;
+  while (blocks <= 1024) {
+    //cout << "fd is " << fd << endl;
+
+    void *buf;
+    ::posix_memalign(&buf, 4096, 4096*blocks);
+    
+    int s = blocks*4096;
+
+    double timeper = 0.0;
+    for (int i=0; i<count; i++) {
+      off64_t so, o = (lrand48() % numblocks) * 4096;
+      //cout << "s = " << s << " o = " << o << endl;
+      //::lseek(fd, o, SEEK_SET);
+      lseek64(fd, o, SEEK_SET);
+      int r = ::read(fd, buf, 4096);
+      //int r = ::read(fd, buf, s);
+      if (r < 0) cout << "r = " << r << " " << strerror(errno) << endl;
+
+      int range = 1000000/4096;
+      so = o + 4096*((rand() % range) );//- range/2);
+      //cout << o << " " << so << " " << (so-o) << endl;
+
+      utime_t start = g_clock.now();
+      lseek64(fd, so, SEEK_SET);
+      r = ::read(fd, buf, blocks*4096);
+      utime_t end = g_clock.now();
+      timeper += (end-start);
+    }
+    
+    timeper /= count;
+    cout << blocks << "\t" << s << "\t" << (double)timeper << endl;
+
+    blocks *= 2;
+    free(buf);
+  }
+
+  close(fd);  
+
+}
+
-- 
2.39.5