Archive for Represent

There’s safe and then there’s safe – Let’s talk RAID

// March 1st, 2010 // 1 Comment » // Rambling, Represent, tech

There’s a lot of information out there about using RAID arrays for drive redundancy or speed or both. And one thing I hear a lot is, “Yeah, I read it. But what does it mean to me?” If you’re a video professional, an animator, a photographer or any number of professions where you generate and use a lot of data, you’ve looked into storage options and, unless you’re looking for something like a ReadyNAS or a Drobo, RAID keeps coming up as ‘the way to go’.

What you probably want more than anything else from this hypothetical storage system is safety. Redundancy. Speed may be important, to varying degrees, but not losing your data along the way is paramount. So what do you need? And what the heck are all those levels and types and why do you need to care?

If you’re someone who just needs to get stuff done and doesn’t want to spend a lot of time sorting all that out, I’m here to help. Assuming you trust me… *grin* So here’s the short course. Skip straight to the graphic if you want. But hopefully you’ll at least skim the following.

CONTROLLER TYPE
Hardware RAID on a controller card is better than software/firmware RAID on a controller card. Software RAID on a dedicated controller is [usually] better than software RAID done by the operating system. The latter depends on how well the OS knows its local hardware. For example, software RAID on a Mac Pro is likely better than most software RAID cards. But that’s the exception, not the rule. A dedicated controller doing hardware RAID is always better. And always more expensive.

LEVELS
This is the bit that’s most confusing to many. What RAID levels signify is the method used to make the data on multiple disks redundant. And, in general, the higher the number the more ’safe’ your data is and the better the methodology. That’s not 100% true, actually, I’ll take RAID1 over RAID3 any day, but for our purposes here, let’s forget about RAID levels 2 through 4. And 0 is right out… mostly. Sort of.

Hang on. We’ll sort all of that out in a sec. Trust me.

RAID 1 is a method for mirroring drives. The most common example is two drives, one mirroring (an exact duplicate) of the other. If one drive fails, the other can soldier on. Yield Example: Two 1TB disks yield 1TB of space.

RAID 5 is three or more drives with the data spread out in such a way that if any one drive fails, the array can continue on until the drive is replaced. Several popular proprietary methods (Netgear’s X-RAID, Drobo’s BeyondRAID, etc.) are similar to RAID 5 but may offer some added benefits, depending on your need. Yield Example: Three 1TB discs yields 2TB of space.

RAID 6 is four or more drives which works similarly to RAID 5, but can tolerate up to two drive failures simultaneously. Yield Example: Four 1TB drives yields 2TB of space. Five 1TB drives yields 3TB of space.

RAID 1+0 (or RAID 10) combines the best of RAID 1 and RAID 0 (a level which provides speed, but no safety whatsoever) along with parity (striping) like RAID 5 or 6. Multiple mirrored sets can be striped together for very high redundancy without sacrificing speed. Requires an even number of drives (4 or more). Yield Example: Four 1TB drives yields 2TB of space (but spectacularly redundant data!).

BACKUP
And all of these types of RAID control are better when paired with some sort of backup. That’s right… as the saying goes, RAID is not backup. If you build a RAID array, back it up. If you don’t, while your chances of data loss might be decreased, they’re not alleviated. If you have 1 copy of something, it’s in peril. 2 copies, it’s backed up. 3 copies, you’re serious about your data.

ONE MORE THING
Port multiplication. If you’re looking at SATA enclosures, you’ve likely seen this mentioned (or heard someone try to scare you off from it). It’s always better to have every SATA drive connected to it’s own line (channel), but sometimes… sometimes that’s just not in the budget. Port multiplying enclosures (and controllers that support PM) are a necessary evil when you can’t buy your way to where you’d like to be. Just to where you hope you’ll get by. I freely admit there’s a PM box hanging off my Mac Pro. It’s used to back up my internal RAID. I see that as a justifiable risk-to-expense decision.

The primary cons for port multiplication are:
1) The maximum speed attainable will be that of the channel, not the box. So don’t expect to get more than 300 MB/s (and plan for less, PM has additional overhead which translates into speed penalties) from any PM box. Think of it a s splitter, with all those drives sharing a pipe meant for a single drive.
2) Some controllers do PM better than others. If you need to scrimp on the enclosure, try not to scrimp on the card. In port multiplication, only one drive can be talk/be talked to at a time and there’s a lot of talking to be done to handle that big flow coming into that small pipe.

Like I said. If you gotta do it, do it. But go into it knowing you’re on the razor’s edge. So plan accordingly (Backups! Unless, of course, this IS the backup device for a more robust array) and don’t set your expectations levels the same as you would for a multi-channel enclosure.

LET’S GET TO IT
So what do you need? What can you afford? What are you willing to give up or not give up? Well, here’s that graphic I promised. Hope it helps.

That middle line is what I like to think of as the ‘make or break’ line. Once you’ve passed that line, then you can start sleeping better at night. But, really, it all depends on your needs and means. Do the best you can. I hope this post helps you sort out what that is.
raidsafety
Legend: H/W = Hardware RAID – S/W = Software RAID – OS S/W = Operating System S/W RAID – BU = Backup

Maggie 3/1/10

Disk Test Results Round 2

// July 16th, 2008 // No Comments » // Rants, Represent, tech

I’ve finished the tests I’d planned and the results are posted in the PDF linked here.
(I’ve updated this since yesterday into one document with added notes, so grab the latest copy.)

In the end, Seagate trounces the competition on performance. However, the second place Samsung disk is still a strong contender, especially where price is an issue. Quite frankly, these are the only two 1TB disks I’ll be recommending to anyone for any sort of capture or editing. Well… actually, I’ll be recommending 4 disks: the two winning models here and their cheaper non-enterprise versions. You’ll have to decide for yourself which best fits your needs and pocketbook.

For us, the 4 Seagates will go into a rack unit and be put into daily use offloading backups.
The 4 Samsungs will go in a new Mac Pro for edit/capture.

Disk Test Results (final)

I’m glad I could share this info and I hope someone finds it useful.
Maggie

Disk Test Results Round 1

// July 11th, 2008 // No Comments » // Raves, Represent, tech

And the winner is… well, that depends on what you’re looking for in a 1TB drive. The clear, overall winner was the Seagate ST31000340NS. It won in overall speed and in sheer ‘clockwork-like’ consistency. But hot on its heels was the Samsung Spinpoint F1 RAID. Not only is this drive cheaper and still ‘enterprise grade’, it also has a consumer-level sibling with nearly identical specs for around $170! That spells bargain, to me.

Have a look at the numbers yourself here: DiskTestResults.pdf
(For more info on what and why, see this post)

I should give special props to the Western Digital ‘Green Power’ drive. It’s not going to win any speed contests, but this drive does draw significantly less power _and_ it runs cooler than the average drive. I tested one in a NAS full of Seagates and the WD drive consistently ran 10 degrees cooler! Take that, Al Gore!

And stay tuned for more shootout between the Seagate and Samsung next week. I’ll be testing a 4 drive conifguration in both internal bays of the Mac Pro as well as using e-SATA via a RocketRaid 2314 controller. And… maybe more if I’m not knackered!

For now… enjoy the weekend, peeps!

UPDATE: For those interested in pricing on the drives as mentioned, here are links from my “go to” drive suppliers for both the enterprise and consumer models of the top two:

Seagate ST31000340NS (~ $270)
Seagate ST31000340AS (~ $215)
Samsung HE103UJ (~ $238)
Samsung HD103UJ (~ $168)

Tim Russert, the Internet loved you

// June 13th, 2008 // No Comments » // Represent

Tim Russert has died. But all around the Internet I’m seeing loving, sad and poignant tributes to him. So to his family and friends who are mourning him today, please know that the Internet mourns with you. We’ve lost a great champion of fair reporting and commentary.

The Internet and America will miss you, Tim Russert. We truly will. Thank you for everything.

In Honor of Pants

// May 19th, 2008 // No Comments » // Represent

In honor of the special pants of that inimitable raconteur and beloved pundit, my friend/acquaintance/culinary cruise director/whatever-you-prefer Andy Ihnatko,
I present a re-telling of Jonathan Coulton’s ‘Mr. Fancy Pants’. *ahem*

Chances are your pants are not as tactical as those
Ordered from the Internet by Andy Ihnatko
They’re functional but generously fitted in the groin
You can roll them up or down
Got zippers by the pound
He’s wearing Internet pants

You look in every catalog you shop at every store
but never find the perfect pair of pants you’re looking for
So you ask the Internet to recommend the best
The best in terms of fit
Can hold a ton of shit
You’re looking for Internet Pants

Sing a little praise for Andy’s Internet Pants
They’re tactical
And practical
With pockets deep
And wide

He makes the big announcement that he’s found the perfect pair
From all the multitudes of pants that he could choose to wear
If you’re the lucky sod who recommended them to him
You deserve a big award or
A place on IhnatCorp’s board
‘Cause Andy loves his Internet Pants

Sing a little praise for Andy’s Internet Pants
They transport DVDs.
‘Round ten with ease
With pockets so deep
And wide…

Mac Camp Boston = unconference

// May 1st, 2008 // No Comments » // Represent

Mac Camp Boston (for which no camping is involved) is being held May 10th.
It will be organized, or is that un-organized, as an unconference in, I believe, the BarCamp style.

Go. Sign up already!
http://maccampboston.com

They’ll be having a meet and greet the night before at BetaHouse.

Playing with WP media…

// March 29th, 2008 // No Comments » // Represent

Wordpress 2.5 includes new media tools so that you can add images, videos or music to a post. I thought I’d give it a go here and see how it works. So, here’s a themed post with a mix I did a while back in Soundtrack Pro featuring a Daft Punk sample _and_ a drawing I did of Bangalter from Daft Punk for a thing called the Baby Grind (it’s like the Daily Grind, but more relaxed).
If you like the pic enough, you can buy it on t-shirt here.

The song – click to play in browser or right-click to download: Half Daft (mp3)

Bangalter
 

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