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Go Cry on Somebody Else's Shoulder: MongoDB is fine

blog.slyphon.com

11–20 of 54 posts

Re: Go Cry on Somebody Else's Shoulder: MongoDB is fine

#11
post #3

remind me on the arguments of which programming language is the best. There is no best technology. Different technologies are designed for different engineering problems. You can't really blame the technology when you are choosing the wrong tools for your problem.

And there are some tools that are shit, and are unfit for every project.

We should never forget that, too. Even in carpentry, there are badly made hammers.

Re: Go Cry on Somebody Else's Shoulder: MongoDB is fine

#12
post #9

Mongo is fine until it's not. It's been fine for us for many months, but once you hit its limitations, it's pretty horrible. We're in this situation right now and we're seriously considering moving back to MySQL or Postgres. Basically, "it doesn't scale" unless you throw tons of machines/shards at it. Once they fix a few of their main issues such as the global write lock and fix many of the bugs, it could become an o…

Have you considered Riak? (I ask mostly because I've been looking at both, having a little MongoDB experience but having heard great things about Riak.)

Re: Go Cry on Somebody Else's Shoulder: MongoDB is fine

#13
Anecdotes like the one from the article that ended with "The one thing that didn’t flinch was MongoDB" don't convince me one bit. When something else between the end user is a bottleneck it would be silly to assume that is the only problem in the entire system. Who is to say that if the load balancers hadn't been configured differently, or higher spec'd that their MongoDB wouldn't have become a smoldering crater?

Re: Go Cry on Somebody Else's Shoulder: MongoDB is fine

#14
post #4

In my opinion, there is but one feature that a database really must have: whatever data I write into it, if I don't delete it, I want to read it back - unaltered (preferably without needing at least three machines, but I'm willing to compromise) Software that cannot provide this single feature just isn't something I would call database. If it's unsafe default configurations or just bugs. I don't care. Between these t…

But wouldn't you rather pin your mission-critical data to a table and give it a night it will never forget? :-D

http://www.youtube.com/watch?v=b2F-DItXtZs

Re: Go Cry on Somebody Else's Shoulder: MongoDB is fine

#15
post #5

I'm not sure how hosting a video for Gawker builds a lot of credibility for having field tested a database; perhaps there are more details he can provide about how that is a particularly interesting trial for a database. Among other things, that seems like "lots and lots of reads, very few writes" and a "very consistent access pattern regardless" kind of situation.

Ha! Fair point. I thought it was an interesting trial in that all updates to our user data wound up being published into MongoDB. All the other tools we'd tried for this purpose, CouchDB, MySQL with both MyISAM and InnoDB and even "thousands of .js files in a hashed directory structure" didn't perform as well. It allowed us to shift the load from our MySQL database to "something else" as during our spikes we were getting killed. It was a read-heavy workload in that case.

The thing that struck me about the original post was how it seemed some of the complaints were just normal things that people learn when dealing with clusters under load. "Adding a shard under heavy load is a nightmare." Well, I mean, duh. If you add a shard and the cluster has to rebalance, you're adding load. It's like how you're more likely to get a disk failure during a RAID rebuild. The correct time to add a shard is during the off hours.

Re: Go Cry on Somebody Else's Shoulder: MongoDB is fine

#16
post #6

The author would have us believe that it's unfair to pick on any piece of software because it "all sucks." They'd also have us believe that complaining about your data disappearing in MongoDB is an unfair criticism, and then takes the logical leap that judging the destruction of data and buggy software somehow has something to do with your own ability to create backups. Generally speaking the people who have been bur…

As he highlights, it is software it will likely have bugs

Re: Go Cry on Somebody Else's Shoulder: MongoDB is fine

#17
Isn't this the same company staffed with the brilliant engineers that used a password scheme so braindead all their users passwords got cleartext'd?

Yeah, right.

Not only are his arguments void, but the anecdote used to back up the "mongo is fine, f off!" message is laughable.

Re: Go Cry on Somebody Else's Shoulder: MongoDB is fine

#18
post #6

The author would have us believe that it's unfair to pick on any piece of software because it "all sucks." They'd also have us believe that complaining about your data disappearing in MongoDB is an unfair criticism, and then takes the logical leap that judging the destruction of data and buggy software somehow has something to do with your own ability to create backups. Generally speaking the people who have been bur…

As he highlights, it is software it will likely have bugs

Yes, but i've been using oracle databases for almost a decade and have never known it to drop data on the floor through bugs (only through user error). Not saying it doesn't happen, just that it's not a common event. It seems with mongo you should expect dataloss.

Re: Go Cry on Somebody Else's Shoulder: MongoDB is fine

#19
I hate to break it to the poster (and I would if they hadn’t chickened out and actually put their name on their post) but software has bugs.

This is not a valid excuse. This is like running a red light, smashing into someone, and then telling them "hey, you should have looked before entering the intersection... you should know that people sometimes run red lights".

Yes, you should have backups. No, that doesn't make data-loss bugs any more excusable.

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