1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
|
/*
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*
*/
#include "qpid/broker/PriorityQueue.h"
#include "qpid/broker/Queue.h"
#include "qpid/broker/QueuedMessage.h"
#include "qpid/framing/reply_exceptions.h"
#include <cmath>
namespace qpid {
namespace broker {
PriorityQueue::PriorityQueue(int l) :
levels(l) {}
bool PriorityQueue::deleted(const QueuedMessage& message)
{
Index::iterator i = messages.find(message.position);
if (i != messages.end()) {
//remove from available list if necessary
if (i->second.status == QueuedMessage::AVAILABLE) {
Available::iterator j = std::find(available.begin(), available.end(), &i->second);
if (j != available.end()) available.erase(j);
}
//remove from messages map
messages.erase(i);
return true;
} else {
return false;
}
}
size_t PriorityQueue::size()
{
return available.size();
}
void PriorityQueue::release(const QueuedMessage& message)
{
Index::iterator i = messages.find(message.position);
if (i != messages.end() && i->second.status == QueuedMessage::ACQUIRED) {
i->second.status = QueuedMessage::AVAILABLE;
//insert message back into the correct place in available queue, based on priority:
Available::iterator j = upper_bound(available.begin(), available.end(), &i->second, boost::bind(&PriorityQueue::compare, this, _1, _2));
available.insert(j, &i->second);
}
}
bool PriorityQueue::acquire(const framing::SequenceNumber& position, QueuedMessage& message)
{
Index::iterator i = messages.find(position);
if (i != messages.end() && i->second.status == QueuedMessage::AVAILABLE) {
i->second.status = QueuedMessage::ACQUIRED;
message = i->second;
//remove it from available list (could make this faster by using ordering):
Available::iterator j = std::find(available.begin(), available.end(), &i->second);
assert(j != available.end());
available.erase(j);
return true;
} else {
return false;
}
}
bool PriorityQueue::find(const framing::SequenceNumber& position, QueuedMessage& message)
{
Index::iterator i = messages.find(position);
if (i != messages.end() && i->second.status == QueuedMessage::AVAILABLE) {
message = i->second;
return true;
} else {
return false;
}
}
bool PriorityQueue::browse(const framing::SequenceNumber& position, QueuedMessage& message, bool unacquired)
{
Index::iterator i = messages.lower_bound(position+1);
if (i != messages.end() && (i->second.status == QueuedMessage::AVAILABLE || (!unacquired && i->second.status == QueuedMessage::ACQUIRED))) {
message = i->second;
return true;
} else {
return false;
}
}
bool PriorityQueue::consume(QueuedMessage& message)
{
if (!available.empty()) {
QueuedMessage* next = available.front();
messages[next->position].status = QueuedMessage::ACQUIRED;
message = *next;
available.pop_front();
return true;
} else {
return false;
}
}
bool PriorityQueue::compare(const QueuedMessage* a, const QueuedMessage* b) const
{
int priorityA = getPriorityLevel(*a);
int priorityB = getPriorityLevel(*b);
if (priorityA == priorityB) return a->position < b->position;
else return priorityA > priorityB;
}
bool PriorityQueue::push(const QueuedMessage& added, QueuedMessage& /*not needed*/)
{
Index::iterator i = messages.insert(Index::value_type(added.position, added)).first;
i->second.status = QueuedMessage::AVAILABLE;
//insert message into the correct place in available queue, based on priority:
Available::iterator j = upper_bound(available.begin(), available.end(), &i->second, boost::bind(&PriorityQueue::compare, this, _1, _2));
available.insert(j, &i->second);
return false;//adding a message never causes one to be removed for deque
}
void PriorityQueue::foreach(Functor f)
{
for (Available::iterator i = available.begin(); i != available.end(); ++i) {
f(**i);
}
}
void PriorityQueue::removeIf(Predicate p)
{
for (Available::iterator i = available.begin(); i != available.end();) {
if (p(**i)) {
messages[(*i)->position].status = QueuedMessage::REMOVED;
i = available.erase(i);
} else {
++i;
}
}
}
uint PriorityQueue::getPriorityLevel(const QueuedMessage& m) const
{
uint priority = m.payload->getPriority();
//Use AMQP 0-10 approach to mapping priorities to a fixed level
//(see rule priority-level-implementation)
const uint firstLevel = 5 - uint(std::min(5.0, std::ceil((double) levels/2.0)));
if (priority <= firstLevel) return 0;
return std::min(priority - firstLevel, (uint)levels-1);
}
uint PriorityQueue::getPriority(const QueuedMessage& message)
{
const PriorityQueue* queue = dynamic_cast<const PriorityQueue*>(&(message.queue->getMessages()));
if (queue) return queue->getPriorityLevel(message);
else return 0;
}
}} // namespace qpid::broker
|
