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Does everyone hate MongoDB?

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Re: Does everyone hate MongoDB?

#111

Post by taligent »

mun2mun wrote: post #97
taligent wrote: post #88

Earlier quoted context omitted.

> But unfortunately they seemed to spit in the face of DBAs and Ops people a long time ago by proclaiming them to be unnecessary and archaic. WTF ? I have never heard 10gen say anything remotely like this. And it surely hasn't come across in their marketing. I mean seriously. Which developer thinks that in a production environment they are going to be the ones supporting the database ? Nobody. > If MongoDB experts ca…

> But unfortunately they seemed to spit in the face of DBAs and Ops people a long time ago by proclaiming them to be unnecessary and archaic. >>WTF ? I have never heard 10gen say anything remotely like this. From the "Ease of use" section of their Philosophy page http://www.mongodb.org/display/DOCS/Philosophy , This means that MongoDB works right out of the box, and you can dive right into developing your application…

How on earth do you equate that statement with "we don't need a DBA when we get into production" ?

Do you need a DBA to get MySQL running ? No. Oracle ? No. SQL Server ? No. That's all it means. Normal people understand that there is a difference between getting something running and deploying it into production.

Re: Does everyone hate MongoDB?

#112

Post by taligent »

Devilboy wrote: post #99
taligent wrote: post #88

Earlier quoted context omitted.

> But unfortunately they seemed to spit in the face of DBAs and Ops people a long time ago by proclaiming them to be unnecessary and archaic. WTF ? I have never heard 10gen say anything remotely like this. And it surely hasn't come across in their marketing. I mean seriously. Which developer thinks that in a production environment they are going to be the ones supporting the database ? Nobody. > If MongoDB experts ca…

> The fact that you base your impression of MongoDB based on ZERO evidence just conjecture that the slowness of their site is database related says a lot about you too. There are many other reasons it could equally be: app server, network etc. Those other things are trivial to fix (e.g. add more app servers) so I too think that it's safe to assume it's probably the data store's fault. > But it does 'just work' that's…

None of what you said makes ANY sense. Have you ever actually scaled an app before ?

Adding more app servers increases the number of requests you can handle. It doesn't make slow apps or latency faster. Both of those are possible causes for why certain requests may be slower. It's not necessarily a database problem.

> Did you read the article?

Yes. I read the documentation before installing MongoDB so I haven't had any problems (so far).

Re: Does everyone hate MongoDB?

#113

Post by mun2mun »

taligent wrote: post #111
mun2mun wrote: post #97

Earlier quoted context omitted.

> But unfortunately they seemed to spit in the face of DBAs and Ops people a long time ago by proclaiming them to be unnecessary and archaic. >>WTF ? I have never heard 10gen say anything remotely like this. From the "Ease of use" section of their Philosophy page http://www.mongodb.org/display/DOCS/Philosophy , This means that MongoDB works right out of the box, and you can dive right into developing your application…

How on earth do you equate that statement with "we don't need a DBA when we get into production" ? Do you need a DBA to get MySQL running ? No. Oracle ? No. SQL Server ? No. That's all it means. Normal people understand that there is a difference between getting something running and deploying it into production.

Point me a doc(or a tiny little red note link, like in the 32 bit installer download page) where 10gen says that you will need a dedicated MongoDB DBA to maintain production server. You see 10gen marketing machine have successfully created a perception that MongoDB is so much magical that you don't have to worry about data. New programmers with less knowledge in RDBMS are buying this argument. And most of the time they start into development just after reading basic tutorial. This the problem GP is trying to address.

Re: Does everyone hate MongoDB?

#114

Post by Cloven »

jeremyjh wrote: post #105
Saavedro wrote: post #95

Earlier quoted context omitted.

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.

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.

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?

Re: Does everyone hate MongoDB?

#115

Post by jamesaguilar »

Zak wrote: post #31

My problems were to do with data-loss and unrecoverable corruption. I didn't write a blog-rant, but maybe I should have. I have since learned that I could have changed some configuration options to make MongoDB less likely to corrupt and/or lose data. I'm still wary though - the fact that the default configuration was prone to unrecoverable data loss suggests that any time I use MongoDB, I must carefully research the…

But if you had to have a safe configuration it would be hard to get the ludicrous performance numbers they tout.

Re: Does everyone hate MongoDB?

#116

Post by Jare »

diego wrote: post #96
jeremyjh wrote: post #93

Earlier quoted context omitted.

Maybe you should learn something from your failure.

Maybe you should make constructive comments instead of making assumptions about what people learn or don't (or what they know or don't, or what has worked for them or hasn't). There are some really disrespectful people in this community.

> There are some really disrespectful people in this community.

Your article begun and ended with sarcastic remarks about the product. Realistically, what kind of response did you expect? The issues described in your article are very real, and very worthy of repeated discussion, but the article itself eschews discussion in favor of pontification, sarcasm and flamebait.

Re: Does everyone hate MongoDB?

#117

Post by fleitz »

MongoDB is kind of like assembler, if you read processor errata sheets for fun you can make some really fast websites. Get that OS, and everything out of the way, just you and the network card.

However, if you just want to write a web app that doesn't lose data it's a really crappy idea and should probably use something creating for solving that problem, like a compiler and web framework.

Re: Does everyone hate MongoDB?

#118

Post by taligent »

PeterisP wrote: post #110
pooriaazimi wrote: post #75

Earlier quoted context omitted.

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…

Shitty defaults are 90% as bad as hardcoded unfixable settings. Defaults usually don't get changed, convention over configuration, etc.

The default for the Java driver changed recently to the Safe mode.

So it does happen.

Re: Does everyone hate MongoDB?

#119

Post by davrosthedalek »

jeremyjh wrote: post #92
pooriaazimi wrote: post #55

Earlier quoted context omitted.

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…

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".

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.

Re: Does everyone hate MongoDB?

#120

Post by davrosthedalek »

lgbr wrote: post #73
diego wrote: post #43

Earlier quoted context omitted.

I like the concept of MongoDB. My main problem (which perhaps is not totally clear from my post, linked in the article) is that there are certain historical conventions about what a database should be. In particular, a database will not have the following default behavior: - return from a write call silently, when the data wasn't written and will not be. If you are going to break conventions on a multi-decade traditi…

> In particular, a database will not have the following default behavior: > - return from a write call silently, when the data wasn't written and will not be There isn't some defined set of rules for how a database should operate. This attitude implies that an asynchronous database should never ever exist. If that's the case, how could I ever use a database for HTTP logging? I can't have every single HTTP request blo…

But even a async database should be able to write something to its log after it discarded the write request. From what I understand from the original article, this did not happen.
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