7 ms·

I haven't got a 32 bit version of Mongo, but people pointed out in the other thread that 32-bit version of mongod displays a little warning every time you start

I haven't got a 32 bit version of Mongo, but people pointed out in the other thread that 32-bit version of mongod displays a little warning every time you start it saying it can handle only 2GB of data. Can you confirm this (because I don't have the 32-bit version installed)? It still stinks, especially because it "silently failed after hitting the threshold", but I personally would feel better about 10gen if this little story is true (i.e. they warn you about it not only in downloads page, but every time you run mongod).

trafficlight 14y ago
> Can you confirm this (because I don't have the 32-bit version installed)? It still stinks, especially because it "silently failed after hitting the threshold", but I personally would feel better about 10gen if this little story is true (i.e. they warn you about it not only in downloads page, but every time you run mongod). Just as a data point, I installed MongoDB on 32-bit Ubuntu 12.04 from the Ubuntu repo. At no point during install or service startup does it say anything. Installing from source may be different.
tedunangst 14y ago
Just installed it on ubuntu 32-bit (apt-get install mongodb). I now have a 32-bit mongodb process running. Minus all of the noise from apt about setting up xulrunner and the 101(!!!) other dependent packages, here's the entirety of the startup messages I see: mongodb start/running, process 13660
- Klinky 14y ago
  Any app that has a warning message will fail to warn you if it's output is rerouted to a log file. This sounds more like an issue with the package maintainers not understanding the limitation and thus not putting in a warning message post install.
werkshy 14y ago
This is true, in the Ubuntu packages this is printed to the default log at /var/log/mongodb/mongodb.log. It is also abundantly clear from the documentation. I struggle to understand how one could deploy a new datastore in production without reading the "getting started" level of documentation or looking in the log at some point. The 2GB 32-bit limit of MongoDB seems like a complete non-issue to me. Wed Sep 19 17:29:21 [initandlisten] MongoDB starting : pid=3765 port=27017 dbpath=/var/lib/mongodb 32-bit host=deepthought Wed Sep 19 17:29:21 [initandlisten] Wed Sep 19 17:29:21 [initandlisten] ** NOTE: when using MongoDB 32 bit, you are limited to about 2 gigabytes of data Wed Sep 19 17:29:21 [initandlisten] ** see http://blog.mongodb.org/post/137788967/32-bit-limitations Wed Sep 19 17:29:21 [initandlisten] ** with --journal, the limit is lower Wed Sep 19 17:29:21 [initandlisten] Wed Sep 19 17:29:21 [initandlisten] db version v2.2.0, pdfile version 4.5 Wed Sep 19 17:29:21 [initandlisten] git version: f5e83eae9cfbec7fb7a071321928f00d1b0c5207 Wed Sep 19 17:29:21 [initandlisten] build info: Linux domU-12-31-39-01-70-B4 2.6.21.7-2.fc8xen #1 SMP Fri Feb 15 12:39:36 EST 2008 i686 BOOST_LIB_VERSION=1_49 Wed Sep 19 17:29:21 [initandlisten] options: { config: "/etc/ mongodb.conf", dbpath: "/var/lib/mongodb", journal: "true", logappend: "true", logpath: "/var/log/mongodb/mongodb.log" } Wed Sep 19 17:29:21 [initandlisten] journal dir=/var/lib/mongodb/journal Wed Sep 19 17:29:21 [initandlisten] recover : no journal files present, no recovery needed Wed Sep 19 17:29:21 [initandlisten] waiting for connections on port 27017 Wed Sep 19 17:29:21 [websvr] admin web console waiting for connections on port 28017
- gaius 14y ago
  The issue is not the limit; it's the silent failure. 32-bit Oracle doesn't do that, it tells you it can't extend the tablespace by raising an exception.
  - pooriaazimi 14y ago
    I'm not trying to defend Mongo, but the reason it doesn't tell you is because you didn't ask for it. If you care about the data (i.e. it's not a log or something that's not very important), you ought to always use "getLastError" to see if your data was actually stored or not (some drivers, like mongoose (for Node.js), just let you specify a simple flag ("safe:true") that does this automatically). A shitty default, no doubt. But it can be changed easily. And "most" drivers offer that. And you usually connect to MongoDB using a driver. http://www.mongodb.org/display/DOCS/getLastError+Command http://www.mongodb.org/display/DOCS/getLastError+Command
    - PeterisP 14y ago
      Shitty defaults are 90% as bad as hardcoded unfixable settings. Defaults usually don't get changed, convention over configuration, etc.
      - taligent 14y ago
        The default for the Java driver changed recently to the Safe mode. So it does happen.
    - rdtsc 14y ago
      > If you care about the data (i.e. it's not a log or something that's not very important), you ought to always use "getLastError" Wait they are promoting this as a database. It is right there in black on yellow "database". I don't know about you but I suspect most people expect databases to try their hardest to protect data. That means also having safe default. As in when I install it and put data in it, by default it should try hardest to make sure that data doesn't get corrupted. If it doesn't, it doesn't deserve to call itself a database. > A shitty default, no doubt. This is not a "oopsie" this is a deliberate lie and misinformation in order to produce fast benchmarks.
diego 14y ago
Confirmed, like others below. Installed on Ubuntu via APT. ~$ sudo service mongodb start mongodb start/running, process 7680
jeremyjh 14y ago
Yes that is true for me, at least using the 10g binaries for Linux (not the Ubuntu package). You get this warning everytime you start the engine. You'd probably have to look at your logs to see it. It is also referenced in the installation documentation. Look guys, MongoDB uses a memory-mapped file. How can it be larger than 2GB on a 32-bit system? There should not need to be "warnings everywhere".
- Saavedro 14y ago
  I think expecting end-users to know or care about the implementation detail of a memory-mapped file is even sillier than all the other silly expectations floating around this thread.
  - jeremyjh 14y ago
    You are right I would not expect end-users to know this. I would expect someone who writes articles about DBMS to know this though.
    - Cloven 14y ago
      would you expect someone who writes articles about DBMSes, or comments in a thread about them, to understand that memory mapped file size is (a) not necessarily limited to address space and (b) 64 bit on 90% of the installations of even 32-bit mongo db?
  - darkarmani 14y ago
    What do you expect end-users to know about oracle or any kind of database tuning?
- davrosthedalek 14y ago
  Maybe stupid question, but isn't there mmap64 and mmap2 with which you can map larger files? You are limited to 2 gigs at a time, but that shouldn't be a complete show stopper.
- DannyBee 14y ago
xaa 14y ago
Why are people running 32-bit OSes in 2012 again?
- mitchty 14y ago
  I run one on my phone daily? Why are you asking a question with an obvious answer of: not everything is 64 bits yet.
- krzyk 14y ago
  Why would I need that when I have <= 4GB RAM? When comparing e.g. 32bit firefox and 64bit one, the first runs much smoother on my system. So if I didn't have 8GB I would install 32bit system. (not to mention that all binaries take less space)

trafficlight 14y ago

> Can you confirm this (because I don't have the 32-bit version installed)? It still stinks, especially because it "silently failed after hitting the threshold", but I personally would feel better about 10gen if this little story is true (i.e. they warn you about it not only in downloads page, but every time you run mongod). Just as a data point, I installed MongoDB on 32-bit Ubuntu 12.04 from the Ubuntu repo. At no point during install or service startup does it say anything. Installing from source may be different.

tedunangst 14y ago

Just installed it on ubuntu 32-bit (apt-get install mongodb). I now have a 32-bit mongodb process running. Minus all of the noise from apt about setting up xulrunner and the 101(!!!) other dependent packages, here's the entirety of the startup messages I see: mongodb start/running, process 13660

Klinky 14y ago
Any app that has a warning message will fail to warn you if it's output is rerouted to a log file. This sounds more like an issue with the package maintainers not understanding the limitation and thus not putting in a warning message post install.

werkshy 14y ago

This is true, in the Ubuntu packages this is printed to the default log at /var/log/mongodb/mongodb.log. It is also abundantly clear from the documentation. I struggle to understand how one could deploy a new datastore in production without reading the "getting started" level of documentation or looking in the log at some point. The 2GB 32-bit limit of MongoDB seems like a complete non-issue to me. Wed Sep 19 17:29:21 [initandlisten] MongoDB starting : pid=3765 port=27017 dbpath=/var/lib/mongodb 32-bit host=deepthought Wed Sep 19 17:29:21 [initandlisten] Wed Sep 19 17:29:21 [initandlisten] ** NOTE: when using MongoDB 32 bit, you are limited to about 2 gigabytes of data Wed Sep 19 17:29:21 [initandlisten] ** see http://blog.mongodb.org/post/137788967/32-bit-limitations Wed Sep 19 17:29:21 [initandlisten] ** with --journal, the limit is lower Wed Sep 19 17:29:21 [initandlisten] Wed Sep 19 17:29:21 [initandlisten] db version v2.2.0, pdfile version 4.5 Wed Sep 19 17:29:21 [initandlisten] git version: f5e83eae9cfbec7fb7a071321928f00d1b0c5207 Wed Sep 19 17:29:21 [initandlisten] build info: Linux domU-12-31-39-01-70-B4 2.6.21.7-2.fc8xen #1 SMP Fri Feb 15 12:39:36 EST 2008 i686 BOOST_LIB_VERSION=1_49 Wed Sep 19 17:29:21 [initandlisten] options: { config: "/etc/ mongodb.conf", dbpath: "/var/lib/mongodb", journal: "true", logappend: "true", logpath: "/var/log/mongodb/mongodb.log" } Wed Sep 19 17:29:21 [initandlisten] journal dir=/var/lib/mongodb/journal Wed Sep 19 17:29:21 [initandlisten] recover : no journal files present, no recovery needed Wed Sep 19 17:29:21 [initandlisten] waiting for connections on port 27017 Wed Sep 19 17:29:21 [websvr] admin web console waiting for connections on port 28017

gaius 14y ago
The issue is not the limit; it's the silent failure. 32-bit Oracle doesn't do that, it tells you it can't extend the tablespace by raising an exception.
- pooriaazimi 14y ago
  I'm not trying to defend Mongo, but the reason it doesn't tell you is because you didn't ask for it. If you care about the data (i.e. it's not a log or something that's not very important), you ought to always use "getLastError" to see if your data was actually stored or not (some drivers, like mongoose (for Node.js), just let you specify a simple flag ("safe:true") that does this automatically). A shitty default, no doubt. But it can be changed easily. And "most" drivers offer that. And you usually connect to MongoDB using a driver. http://www.mongodb.org/display/DOCS/getLastError+Command http://www.mongodb.org/display/DOCS/getLastError+Command
  - PeterisP 14y ago
    Shitty defaults are 90% as bad as hardcoded unfixable settings. Defaults usually don't get changed, convention over configuration, etc.
    - taligent 14y ago
      The default for the Java driver changed recently to the Safe mode. So it does happen.
  - rdtsc 14y ago
    > If you care about the data (i.e. it's not a log or something that's not very important), you ought to always use "getLastError" Wait they are promoting this as a database. It is right there in black on yellow "database". I don't know about you but I suspect most people expect databases to try their hardest to protect data. That means also having safe default. As in when I install it and put data in it, by default it should try hardest to make sure that data doesn't get corrupted. If it doesn't, it doesn't deserve to call itself a database. > A shitty default, no doubt. This is not a "oopsie" this is a deliberate lie and misinformation in order to produce fast benchmarks.

diego 14y ago

Confirmed, like others below. Installed on Ubuntu via APT. ~$ sudo service mongodb start mongodb start/running, process 7680

jeremyjh 14y ago

Yes that is true for me, at least using the 10g binaries for Linux (not the Ubuntu package). You get this warning everytime you start the engine. You'd probably have to look at your logs to see it. It is also referenced in the installation documentation. Look guys, MongoDB uses a memory-mapped file. How can it be larger than 2GB on a 32-bit system? There should not need to be "warnings everywhere".

Saavedro 14y ago
I think expecting end-users to know or care about the implementation detail of a memory-mapped file is even sillier than all the other silly expectations floating around this thread.
- jeremyjh 14y ago
  You are right I would not expect end-users to know this. I would expect someone who writes articles about DBMS to know this though.
  - Cloven 14y ago
    would you expect someone who writes articles about DBMSes, or comments in a thread about them, to understand that memory mapped file size is (a) not necessarily limited to address space and (b) 64 bit on 90% of the installations of even 32-bit mongo db?
- darkarmani 14y ago
  What do you expect end-users to know about oracle or any kind of database tuning?
davrosthedalek 14y ago
Maybe stupid question, but isn't there mmap64 and mmap2 with which you can map larger files? You are limited to 2 gigs at a time, but that shouldn't be a complete show stopper.
DannyBee 14y ago

xaa 14y ago

Why are people running 32-bit OSes in 2012 again?

mitchty 14y ago
I run one on my phone daily? Why are you asking a question with an obvious answer of: not everything is 64 bits yet.
krzyk 14y ago
Why would I need that when I have <= 4GB RAM? When comparing e.g. 32bit firefox and 64bit one, the first runs much smoother on my system. So if I didn't have 8GB I would install 32bit system. (not to mention that all binaries take less space)