summaryrefslogtreecommitdiff
path: root/src/mongo/db/startup_warnings.cpp
blob: 930e08dec10f19f40bd3e2ebe7898680cbfd9042 (plain)
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
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
/**
*    Copyright (C) 2013 10gen Inc.
*
*    This program is free software: you can redistribute it and/or  modify
*    it under the terms of the GNU Affero General Public License, version 3,
*    as published by the Free Software Foundation.
*
*    This program is distributed in the hope that it will be useful,
*    but WITHOUT ANY WARRANTY; without even the implied warranty of
*    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
*    GNU Affero General Public License for more details.
*
*    You should have received a copy of the GNU Affero General Public License
*    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*
*    As a special exception, the copyright holders give permission to link the
*    code of portions of this program with the OpenSSL library under certain
*    conditions as described in each individual source file and distribute
*    linked combinations including the program with the OpenSSL library. You
*    must comply with the GNU Affero General Public License in all respects
*    for all of the code used other than as permitted herein. If you modify
*    file(s) with this exception, you may extend this exception to your
*    version of the file(s), but you are not obligated to do so. If you do not
*    wish to do so, delete this exception statement from your version. If you
*    delete this exception statement from all source files in the program,
*    then also delete it in the license file.
*/

#include "mongo/platform/basic.h"

#include "mongo/db/startup_warnings.h"

#include <boost/filesystem/operations.hpp>
#include <fstream>

#include "mongo/db/storage_options.h"
#include "mongo/util/log.h"
#include "mongo/util/processinfo.h"
#include "mongo/util/version.h"

namespace mongo {

    //
    // system warnings
    //
    void logStartupWarnings() {
        // each message adds a leading and a trailing newline

        bool warned = false;
        {
            const char * foo = strchr(versionString , '.') + 1;
            int bar = atoi(foo);
            if ((2 * (bar / 2)) != bar) {
                log() << startupWarningsLog;
                log() << "** NOTE: This is a development version (" << versionString
                      << ") of MongoDB." << startupWarningsLog;
                log() << "**       Not recommended for production." << startupWarningsLog;
                warned = true;
            }
        }

        if (sizeof(int*) == 4) {
            log() << startupWarningsLog;
            log() << "** NOTE: This is a 32 bit MongoDB binary." << startupWarningsLog;
            log() << "**       32 bit builds are limited to less than 2GB of data "
                  << "(or less with --journal)." << startupWarningsLog;
            if (!storageGlobalParams.dur) {
                log() << "**       Note that journaling defaults to off for 32 bit "
                      << "and is currently off." << startupWarningsLog;
            }
            log() << "**       See http://dochub.mongodb.org/core/32bit" << startupWarningsLog;
            warned = true;
        }

        if (!ProcessInfo::blockCheckSupported()) {
            log() << startupWarningsLog;
            log() << "** NOTE: your operating system version does not support the method that "
                  << "MongoDB" << startupWarningsLog;
            log() << "**       uses to detect impending page faults." << startupWarningsLog;
            log() << "**       This may result in slower performance for certain use "
                  << "cases" << startupWarningsLog;
            warned = true;
        }
#ifdef __linux__
        if (boost::filesystem::exists("/proc/vz") && !boost::filesystem::exists("/proc/bc")) {
            log() << startupWarningsLog;
            log() << "** WARNING: You are running in OpenVZ which can cause issues on versions "
                  << "of RHEL older than RHEL6." << startupWarningsLog;
            warned = true;
        }

        bool hasMultipleNumaNodes = false;
        try {
            hasMultipleNumaNodes = boost::filesystem::exists("/sys/devices/system/node/node1");
        } catch(boost::filesystem::filesystem_error& e) {
            log() << startupWarningsLog;
            log() << "** WARNING: Cannot detect if NUMA interleaving is enabled. "
                  << "Failed to probe \"" << e.path1().string() << "\": " << e.code().message()
                  << startupWarningsLog;
        }
        if (hasMultipleNumaNodes) {
            // We are on a box with a NUMA enabled kernel and more than 1 numa node (they start at
            // node0)
            // Now we look at the first line of /proc/self/numa_maps
            //
            // Bad example:
            // $ cat /proc/self/numa_maps
            // 00400000 default file=/bin/cat mapped=6 N4=6
            //
            // Good example:
            // $ numactl --interleave=all cat /proc/self/numa_maps
            // 00400000 interleave:0-7 file=/bin/cat mapped=6 N4=6

            std::ifstream f("/proc/self/numa_maps", std::ifstream::in);
            if (f.is_open()) {
                std::string line; //we only need the first line
                std::getline(f, line);
                if (f.fail()) {
                    warning() << "failed to read from /proc/self/numa_maps: "
                              << errnoWithDescription() << startupWarningsLog;
                    warned = true;
                }
                else {
                    // skip over pointer
                    std::string::size_type where = line.find(' ');
                    if ((where == std::string::npos) || (++where == line.size())) {
                        log() << startupWarningsLog;
                        log() << "** WARNING: cannot parse numa_maps line: '" << line << "'"
                              << startupWarningsLog;
                        warned = true;
                    }
                    // if the text following the space doesn't begin with 'interleave', then
                    // issue the warning.
                    else if (line.find("interleave", where) != where) {
                        log() << startupWarningsLog;
                        log() << "** WARNING: You are running on a NUMA machine."
                              << startupWarningsLog;
                        log() << "**          We suggest launching mongod like this to avoid "
                              << "performance problems:" << startupWarningsLog;
                        log() << "**              numactl --interleave=all mongod [other options]"
                              << startupWarningsLog;
                        warned = true;
                    }
                }
            }
        }

        if (storageGlobalParams.dur) {
            std::fstream f("/proc/sys/vm/overcommit_memory", ios_base::in);
            unsigned val;
            f >> val;

            if (val == 2) {
                log() << startupWarningsLog;
                log() << "** WARNING: /proc/sys/vm/overcommit_memory is " << val
                      << startupWarningsLog;
                log() << "**          Journaling works best with it set to 0 or 1"
                      << startupWarningsLog;
            }
        }

        if (boost::filesystem::exists("/proc/sys/vm/zone_reclaim_mode")){
            std::fstream f("/proc/sys/vm/zone_reclaim_mode", ios_base::in);
            unsigned val;
            f >> val;

            if (val != 0) {
                log() << startupWarningsLog;
                log() << "** WARNING: /proc/sys/vm/zone_reclaim_mode is " << val
                      << startupWarningsLog;
                log() << "**          We suggest setting it to 0" << startupWarningsLog;
                log() << "**          http://www.kernel.org/doc/Documentation/sysctl/vm.txt"
                      << startupWarningsLog;
            }
        }
#endif

#if defined(RLIMIT_NPROC) && defined(RLIMIT_NOFILE)
        //Check that # of files rlmit > 1000 , and # of processes > # of files/2
        const unsigned int minNumFiles = 1000;
        const double filesToProcsRatio = 2.0;
        struct rlimit rlnproc;
        struct rlimit rlnofile;

        if(!getrlimit(RLIMIT_NPROC,&rlnproc) && !getrlimit(RLIMIT_NOFILE,&rlnofile)){
            if(rlnofile.rlim_cur < minNumFiles){
                log() << startupWarningsLog;
                log() << "** WARNING: soft rlimits too low. Number of files is "
                        << rlnofile.rlim_cur
                        << ", should be at least " << minNumFiles << startupWarningsLog;
            }

            if(false){
                // juse to make things cleaner
            }
#ifdef __APPLE__
            else if(rlnproc.rlim_cur >= 709){
                // os x doesn't make it easy to go higher
                // ERH thinks its ok not to add the warning in this case 7/3/2012
            }
#endif
            else if(rlnproc.rlim_cur < rlnofile.rlim_cur/filesToProcsRatio){
                log() << startupWarningsLog;
                log() << "** WARNING: soft rlimits too low. rlimits set to "
                      << rlnproc.rlim_cur << " processes, "
                      << rlnofile.rlim_cur << " files. Number of processes should be at least "
                      << rlnofile.rlim_cur/filesToProcsRatio << " : "
                      << 1/filesToProcsRatio << " times number of files." << startupWarningsLog;
            }
        } else {
            log() << startupWarningsLog;
            log() << "** WARNING: getrlimit failed. " << errnoWithDescription()
                  << startupWarningsLog;
        }
#endif

#ifdef _WIN32
        ProcessInfo p;

        if (p.hasNumaEnabled()) {
            log() << startupWarningsLog;
            log() << "** WARNING: You are running on a NUMA machine."
                << startupWarningsLog;
            log() << "**          We suggest disabling NUMA in the machine BIOS " 
                << startupWarningsLog;
            log() << "**          by enabling interleaving to avoid performance problems. " 
                << startupWarningsLog;
            log() << "**          See your BIOS documentation for more information." 
                << startupWarningsLog;
            warned = true;
        }
#endif // #ifdef _WIN32

        if (warned) {
            log() << startupWarningsLog;
        }
    }
} // namespace mongo