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Comment: Re:It's the contents of the files... (Score 1) 396

by Marsell (#47239179) Attached to: One Developer's Experience With Real Life Bitrot Under HFS+

The irony of your calling someone else clueless...

Drives do indeed have checksums on their blocks. That does not prevent them from sometimes feeding you back garbage anyway -- see misdirected and phantom reads and writes. Since ZFS uses a self-validating merkle tree, whereas disk checksums live in the same block as the data, ZFS is largely immune to this problem.

If you've worked with disks any length of time, as in actually trying to write a robust filesystem, you'd know that disks sometimes lie. They usually work but every now and then they do the most ridiculous things, due to mechanical, electrical or firmware problems. That's why filesystems like ZFS were created (what, you thought Sun spent man-decades of expert time on it for giggles?). kthreadd is correct.

Please just stay away from storage. The topic is much more complicated than you make it out to be.

Comment: Re:Accept, don't fight, systemd (Score 2) 533

by Marsell (#46956029) Attached to: Ask Slashdot: Practical Alternatives To Systemd?

It was called Slowlaris in large part because of STREAMS support, which was mandatory in SUS v1 and v2. I find it a bit sad that Solaris historically was ragged upon because it basically tried to follow de jure standards to a T, and backwards-compatibility was a high priority.

But that's a different discussion. Nowadays both Linux and Solaris derivatives have similar computational overheads: sometimes Linux comes out ahead, and sometimes Solaris. I think system administration is completely in favour of Solaris, but we obviously have differing opinions on this.

Comment: Re:Accept, don't fight, systemd (Score 1) 533

by Marsell (#46955735) Attached to: Ask Slashdot: Practical Alternatives To Systemd?

Solaris was abandoned for reasons completely unrelated to SMF and its various technologies. If anything, Solaris 10 was a decade ahead of its time (DTrace, ZFS, zones, crossbow).

It's just that by the time Solaris was opened, the mindshare and momentum was vastly with Linux. It never stood a chance, completely unrelated to its technical merits, and Oracle closing it again just sealed the deal.

Having said that, illumos (an OSS version of Solaris that forked a few years back) is awesome and actively developed by several companies making money with its technologies.

Comment: Re:Accept, don't fight, systemd (Score 1) 533

by Marsell (#46955673) Attached to: Ask Slashdot: Practical Alternatives To Systemd?

I hate this stuff, none of my admins remember where the damn log files are because they play with it so rarely.

If you use illumos or Solaris 11.2, svcs -L gives you the path to the service log. I use "grep foo `svcs -L bar`" all the time.

I use SMF a lot, and I've rarely had trouble with it. svcs -vx shows you which services are down (as well as the log path, hello), and you take a look at the log to see what your application is complaining about. I have consistently found it easier to use than init scripts, despite me usually having a very conservative OS bent.

The only thing I don't like about SMF is the XML.

Comment: Solaris name dead, but OSS code lives on (Score 3, Informative) 223

by Marsell (#45948417) Attached to: James Gosling Grades Oracle's Handling of Sun's Tech

While Solaris itself is no longer relevant outside of some enterprise niches, it has an actively-developed OSS fork named "illumos", developed by former-Sun hackers working at several different private companies. There are several distributions -- I use SmartOS in particular, and OmniTI's OmniOS is also excellent.

Comment: Change logs matter (Score 5, Insightful) 162

by Marsell (#45657453) Attached to: Ask Slashdot: To Publish Change Logs Or Not?

Anybody who has run software on a non-trivial scale knows how important changelogs are.

They give you some idea of what to expect, but more importantly let you know whether a problem you're having now has been fixed in the upgrade. Although developers would like everyone to run the newest version of software, in practice you don't touch production systems without good reason. Fixed pain points, and maybe security (depending on isolation) are valid reasons. "Because it's there" is not.

Elimination is a stupid move. It's a triumph of marketing at the cost of we who must run this shit.

Comment: Manta (Score 1) 80

by Marsell (#45559017) Attached to: Ask Slashdot: Scientific Computing Workflow For the Cloud?

If you're willing to look beyond AWS, there's something called Manta out there ( The data rests on some servers, and you submit UNIX map/reduce jobs. The jobs are run on the nodes where the data is resting, you get a full UNIX environment, and you only get charged as you'd expect (compute time, combined with the cheaper at-rest time). It might be a better fit for what you're doing than your proposal, plus it'll likely be faster too due to reduced data movement.

Comment: Re:Why would I even consider using OpenSolaris? (Score 1) 342

by Marsell (#33246772) Attached to: The Future of OpenSolaris Revealed

Backups are necessary. But, you know, it's nice to avoid restoring a backup if you don't need to.

Furthermore, backups don't help with data that flips bits on disk without being noticed, then consumed by the system in some calculation. A lot of filesystems do not notice non-metadata bits flipping, so you could end up end up with false suddenly becoming true in your database, affecting future calculations.

Once you add RAID, failure conditions become yet more complicated, although some of them become less likely. I don't even know where to begin on that one, except that it isn't a panacea.

It's easy to go "F***" if you're clueless.

Comment: Re:Why would I even consider using OpenSolaris? (Score 1) 342

by Marsell (#33245080) Attached to: The Future of OpenSolaris Revealed

Except that Ext and ZFS are in different classes. Ext provides few of the protections that ZFS does.

I'm only aware of two filesystems in the same class: ZFS and Btrfs. I'm looking forward to the day I can use Btrfs on production, but until then there's just ZFS. Ext is a non-contender here.

What the world *really* needs is a good Automatic Bicycle Sharpener.