ceph/branches/sage/pgs/osd/ObjectStore.cc

#include "ObjectStore.h"

#include "config.h"
#include "common/Clock.h"


object_t ObjectStore::age_get_oid() {
    if (!age_free_oids.empty()) {
      object_t o = age_free_oids.front();
      age_free_oids.pop_front();
      return o;
    }
    return age_cur_oid++;
  }

  ssize_t ObjectStore::age_pick_size() {
    ssize_t max = file_size_distn.sample() * 1024;
    return max/2 + (rand() % 100) * max/200 + 1;
  }

  void ObjectStore::age_fill(float pc, utime_t until) {
	bufferptr bp(1024*1024);
	bp.zero();
    bufferlist bl;
    bl.push_back(bp);
    while (1) {
      if (g_clock.now() > until) break;

      struct statfs st;
      statfs(&st);
      float a = (float)(st.f_blocks-st.f_bavail) / (float)st.f_blocks;
      if (a >= pc) {
        dout(10) << "age_fill at " << a << " / " << pc << " stopping" << endl;
        break;
      }

      object_t oid = age_get_oid();

      int b = rand() % 10;
      age_objects[b].push_back(oid);

      ssize_t s = age_pick_size();

      dout(10) << "age_fill at " << a << " / " << pc << " creating " << hex << oid << dec << " sz " << s << endl;

      off_t off = 0;
      while (s) {
        ssize_t t = MIN(s, 1024*1024);
        write(oid, t, off, bl, false);
        off += t;
        s -= t;
      }
      oid++;
    }
  }

  void ObjectStore::age_empty(float pc) {
    int nper = 20;
    int n = nper;
    while (1) {
      struct statfs st;
      statfs(&st);
      float a = (float)(st.f_blocks-st.f_bavail) / (float)st.f_blocks;
      if (a <= pc) {
        dout(10) << "age_empty at " << a << " / " << pc << " stopping" << endl;
        break;
      }

      int b = rand() % 10;
      n--;
      if (n == 0 || age_objects[b].empty()) {
        dout(10) << "age_empty sync" << endl;
        //sync();
        sync();
        n = nper;
        continue;
      }
      object_t oid = age_objects[b].front();
      age_objects[b].pop_front();

      dout(10) << "age_empty at " << a << " / " << pc << " removing " << hex << oid << dec << endl;

      remove(oid);
      age_free_oids.push_back(oid);
    }
  }


  void ObjectStore::age(int time,
                        float high_water,    // fill to this %
          float low_water,     // then empty to this %
          int count,         // this many times
          float final_water,   // and end here ( <= low_water)
          int fake_size_mb) { 
    utime_t until = g_clock.now();
    until.sec_ref() += time;

    while (age_objects.size() < 10) age_objects.push_back( list<object_t>() );

    if (fake_size_mb) {
      int fake_bl = fake_size_mb * 256;
      struct statfs st;
      statfs(&st);
      float f = (float)fake_bl / (float)st.f_blocks;
      high_water = (float)high_water * f;
      low_water = (float)low_water * f;
      final_water = (float)final_water * f;
      dout(10) << "fake " << fake_bl << " / " << st.f_blocks << " is " << f << ", high " << high_water << " low " << low_water << " final " << final_water << endl;
    }

    // init size distn (once)
    if (!did_distn) {
      did_distn = true;
      age_cur_oid = 1;
      file_size_distn.add(1, 19.0758125+0.65434375);
      file_size_distn.add(512, 35.6566);
      file_size_distn.add(1024, 27.7271875);
      file_size_distn.add(2*1024, 16.63503125);
      //file_size_distn.add(4*1024, 106.82384375);
      //file_size_distn.add(8*1024, 81.493375);
      //file_size_distn.add(16*1024, 14.13553125);
      //file_size_distn.add(32*1024, 2.176);
      //file_size_distn.add(256*1024, 0.655938);
      //file_size_distn.add(512*1024, 0.1480625);
      //file_size_distn.add(1*1024*1024, 0.020125); // actually 2, but 32bit
      file_size_distn.normalize();
    }

    // clear
    for (int i=0; i<10; i++)
      age_objects[i].clear();

    for (int c=1; c<=count; c++) {
      if (g_clock.now() > until) break;

      dout(1) << "age " << c << "/" << count << " filling to " << high_water << endl;
      age_fill(high_water, until);
      if (c == count) {
        dout(1) << "age final empty to " << final_water << endl;
        age_empty(final_water);    
      } else {
        dout(1) << "age " << c << "/" << count << " emptying to " << low_water << endl;
        age_empty(low_water);
      }
    }
    dout(1) << "age finished" << endl;
  }