ceph/src/common/DecayCounter.cc
Sage Weil d5a6a251ae DecayCounter: use modern encoding
Signed-off-by: Sage Weil <sage@inktank.com>
Signed-off-by: Greg Farnum <greg@inktank.com>
2013-02-08 13:17:51 -08:00

83 lines
1.8 KiB
C++

// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
// vim: ts=8 sw=2 smarttab
/*
* Ceph - scalable distributed file system
*
* Copyright (C) 2004-2006 Sage Weil <sage@newdream.net>
*
* This is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License version 2.1, as published by the Free Software
* Foundation. See file COPYING.
*
*/
#include "DecayCounter.h"
#include "Formatter.h"
void DecayCounter::encode(bufferlist& bl) const
{
ENCODE_START(4, 4, bl);
::encode(val, bl);
::encode(delta, bl);
::encode(vel, bl);
ENCODE_FINISH(bl);
}
void DecayCounter::decode(const utime_t &t, bufferlist::iterator &p)
{
DECODE_START_LEGACY_COMPAT_LEN(4, 4, 4, p);
if (struct_v < 2) {
double half_life;
::decode(half_life, p);
}
if (struct_v < 3) {
double k;
::decode(k, p);
}
::decode(val, p);
::decode(delta, p);
::decode(vel, p);
DECODE_FINISH(p);
}
void DecayCounter::dump(Formatter *f) const
{
f->dump_float("value", val);
f->dump_float("delta", delta);
f->dump_float("velocity", vel);
}
void DecayCounter::generate_test_instances(list<DecayCounter*>& ls)
{
utime_t fake_time;
DecayCounter *counter = new DecayCounter(fake_time);
counter->val = 3.0;
counter->delta = 2.0;
counter->vel = 1.0;
ls.push_back(counter);
counter = new DecayCounter(fake_time);
ls.push_back(counter);
}
void DecayCounter::decay(utime_t now, const DecayRate &rate)
{
utime_t el = now;
el -= last_decay;
if (el.sec() >= 1) {
// calculate new value
double newval = (val+delta) * exp((double)el * rate.k);
if (newval < .01)
newval = 0.0;
// calculate velocity approx
vel += (newval - val) * (double)el;
vel *= exp((double)el * rate.k);
val = newval;
delta = 0;
last_decay = now;
}
}