psim crush placement sim

1 files changed, 47 insertions, 0 deletions

diff --git a/src/psim.cc b/src/psim.cc
new file mode 100644
index 00000000000..deab7c8aa0d
--- /dev/null
+++ b/src/psim.cc
@@ -0,0 +1,47 @@
+
+#include <iostream>
+
+#include "crush/CrushWrapper.h"
+#include "osd/OSDMap.h"
+#include "config.h"
+#include "include/buffer.h"
+
+int main()
+{
+  /*
+   * you need to create a suitable osdmap first.  e.g., for 40 osds, 
+   * $ ./osdmaptool --createsimple .ceph_monmap 40 --clobber .ceph_osdmap 
+   */
+  bufferlist bl;
+  bl.read_file(".ceph_osdmap");
+  OSDMap osdmap;
+  osdmap.decode(bl);
+
+  int n = osdmap.get_max_osd();
+  int count[n];
+  for (int i=0; i<n; i++) {
+    osdmap.mark_up(i);
+    osdmap.mark_in(i);
+    count[i] = 0;
+  }
+
+  for (int f = 1; f < 1000; f++) {  // files
+    for (int b = 0; b < 4; b++) {   // blocks
+      object_t oid(f, b);
+      //cout << "oid " << oid << std::endl;
+      ceph_object_layout l = osdmap.file_to_object_layout(oid, g_default_file_layout);
+      vector<int> osds;
+      osdmap.pg_to_osds(pg_t(le64_to_cpu(l.ol_pgid)), osds);
+      for (unsigned i=0; i<osds.size(); i++) {
+	//cout << " rep " << i << " on " << osds[i] << std::endl;
+	count[osds[i]]++;
+      }
+    }
+  }
+
+  for (int i=0; i<n; i++) {
+    cout << "osd" << i << "\t" << count[i] << std::endl;
+  }
+  
+  return 0;
+}