-
Notifications
You must be signed in to change notification settings - Fork 5.6k
/
parallel.h
195 lines (151 loc) · 5.6 KB
/
parallel.h
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
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
// parallel.h
/* Copyright 2009 10gen Inc.
*
* Licensed 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.
*/
/**
tools for wokring in parallel/sharded/clustered environment
*/
#include "../stdafx.h"
#include "dbclient.h"
#include "../db/dbmessage.h"
namespace mongo {
/**
* this is a cursor that works over a set of servers
* can be used in serial/paralellel as controlled by sub classes
*/
class ClusteredCursor {
public:
ClusteredCursor( QueryMessage& q );
ClusteredCursor( const string& ns , const BSONObj& q , int options=0 , const BSONObj& fields=BSONObj() );
virtual ~ClusteredCursor();
virtual bool more() = 0;
virtual BSONObj next() = 0;
static BSONObj concatQuery( const BSONObj& query , const BSONObj& extraFilter );
virtual string type() const = 0;
protected:
auto_ptr<DBClientCursor> query( const string& server , int num = 0 , BSONObj extraFilter = BSONObj() );
static BSONObj _concatFilter( const BSONObj& filter , const BSONObj& extraFilter );
string _ns;
BSONObj _query;
int _options;
BSONObj _fields;
bool _done;
};
/**
* holder for a server address and a query to run
*/
class ServerAndQuery {
public:
ServerAndQuery( const string& server , BSONObj extra = BSONObj() , BSONObj orderObject = BSONObj() ) :
_server( server ) , _extra( extra.getOwned() ) , _orderObject( orderObject.getOwned() ){
}
bool operator<( const ServerAndQuery& other ) const{
if ( ! _orderObject.isEmpty() )
return _orderObject.woCompare( other._orderObject ) < 0;
if ( _server < other._server )
return true;
if ( other._server > _server )
return false;
return _extra.woCompare( other._extra ) < 0;
}
string toString() const {
StringBuilder ss;
ss << "server:" << _server << " _extra:" << _extra << " _orderObject:" << _orderObject;
return ss.str();
}
operator string() const {
return toString();
}
string _server;
BSONObj _extra;
BSONObj _orderObject;
};
/**
* runs a query in serial across any number of servers
* returns all results from 1 server, then the next, etc...
*/
class SerialServerClusteredCursor : public ClusteredCursor {
public:
SerialServerClusteredCursor( const set<ServerAndQuery>& servers , QueryMessage& q , int sortOrder=0);
virtual bool more();
virtual BSONObj next();
virtual string type() const { return "SerialServer"; }
private:
vector<ServerAndQuery> _servers;
unsigned _serverIndex;
auto_ptr<DBClientCursor> _current;
};
/**
* runs a query in parellel across N servers
* sots
*/
class ParallelSortClusteredCursor : public ClusteredCursor {
public:
ParallelSortClusteredCursor( const set<ServerAndQuery>& servers , QueryMessage& q , const BSONObj& sortKey );
ParallelSortClusteredCursor( const set<ServerAndQuery>& servers , const string& ns ,
const Query& q , int options=0, const BSONObj& fields=BSONObj() );
virtual ~ParallelSortClusteredCursor();
virtual bool more();
virtual BSONObj next();
virtual string type() const { return "ParallelSort"; }
private:
void _init();
void advance();
int _numServers;
set<ServerAndQuery> _servers;
BSONObj _sortKey;
auto_ptr<DBClientCursor> * _cursors;
BSONObj * _nexts;
};
/**
* tools for doing asynchronous operations
* right now uses underlying sync network ops and uses another thread
* should be changed to use non-blocking io
*/
class Future {
public:
class CommandResult {
public:
string getServer() const { return _server; }
bool isDone() const { return _done; }
bool ok() const {
assert( _done );
return _ok;
}
BSONObj result() const {
assert( _done );
return _res;
}
/**
blocks until command is done
returns ok()
*/
bool join();
private:
CommandResult( const string& server , const string& db , const BSONObj& cmd );
string _server;
string _db;
BSONObj _cmd;
boost::thread _thr;
BSONObj _res;
bool _done;
bool _ok;
friend class Future;
};
static void commandThread();
static shared_ptr<CommandResult> spawnCommand( const string& server , const string& db , const BSONObj& cmd );
private:
static shared_ptr<CommandResult> * _grab;
};
}