Comments for kennygorman.com

Comment on Data clustering in MongoDB using embedded docs by jametong

jametong — Thu, 01 Jul 2010 06:38:19 +0000

you’ve change the data model.

the related postgresql data model should be

userid integer,
file_path_list text

Comment on Cluster data, save cash by Data clustering in MongoDB using embedded docskennygorman.com | kennygorman.com

Fri, 25 Jun 2010 23:13:39 +0000

[...] wrote a while ago about how to cluster data to save cash. This post was geared towards relational stores. But in reality, the technique is applicable to any [...]

Comment on WordPress 3.0 by kgorman

kgorman — Mon, 21 Jun 2010 22:32:35 +0000

Just utilized the new enhanced menu system. Very nice.

Comment on Fusion-io SSD by Disk I/O: PCI Based SSDs « makeitfaster

Disk I/O: PCI Based SSDs « makeitfaster — Thu, 10 Jun 2010 01:57:55 +0000

[...] is not lost. There are capacitors on the board with enough power to finalize any pending writes. Some users have tested powerloss scenarios extensively and have had great success.However, some other users [...]

Comment on Wayback Machine: snapshots still valid technique by Log Buffer #189, A Carnival of the Vanities for DBAs « So Many Oracle Manuals, So Little Time

Fri, 14 May 2010 14:35:27 +0000

[...] across an article that he wrote eight years ago for the May 2002 issue of the NoCOUG Journal about using OS snapshots for backups. The original article discussed only Oracle but Kenny shows how to use the same technique for [...]

Comment on MongoSF Slides by kgorman

kgorman — Mon, 03 May 2010 20:20:46 +0000

Sure, it shouldn’t be getting on there because only the category for PostgreSQL should hit planet. I will hit them up with a reminder.

Comment on MongoSF Slides by Mike Dirolf

Mike Dirolf — Mon, 03 May 2010 19:44:31 +0000

Thanks Kenny! Glad you enjoyed the talk. It was great meeting you and hearing about how MongoDB is fitting in at Shutterfly!

Comment on MongoSF Slides by Jay

Jay — Mon, 03 May 2010 19:34:11 +0000

As exciting as all this NoSQL crap is, could you arrange to keep it off the Planet PostgreSQL feed?

Comment on Dropping ACID by Josh Berkus

Josh Berkus — Sun, 04 Apr 2010 20:33:26 +0000

Kenny,

I don’t disagree with you that recovery-via-replicated data is the right answer for primary data recovery on large web clusters. A hybrid solution which involves recovery from disk combined with catch-up from replicas can be even better; this allows the downed node to be brought back up with a minimum of recovery load on the other servers. Assuming, of course, that disk logging isn’t too much of a performance hit (although asyncronous disk logging could alleviate that).

What I’m asserting instead is that web-scale durability is hard to implement, complex and high-administration (ask Google or Amazon how many engineer-hours they spent on it), and not somehow easier than disk-based durability. Nor is durability-via-replication an excuse for not having a local durability option for a general open source database; what about users who only have a single server?

The real answer for any new database system is to have both replication-based and local durability options, with the ability to enable and disable either, possibly in more than one mode.

Comment on Fusion-io SSD by Josh Berkus

Josh Berkus — Sun, 04 Apr 2010 20:16:57 +0000

Kgorman,

I don’t think that white papers from the vendor prove much except that they thought about the issue, whether or not they did anything about it. Those are marketing pieces. I’d like to see some 3rd-party testing of the lifetime of SSDs under a WAL load on a really busy database.

If you believed Dell’s whitepapers, for example, every server they ship would be perfect.