Please explain minimum write transfer speed

[gentrinity]

Im looking at the benchmarks for disks on THG and Im looking at the WD Caviar SE16 WD500KS as a back up HD. Im very impressed with its performance, since its either that or the Barracuda 750GB, which is $120 bucks more expensive. The performance between the two is close enough to make me feel that I dont need to spend $120 extra for 250GB more, I think 500GB are more than enough for my current needs, especially considering I will get the RAID 0 Raptors 150, so thats 300GB more I can use for data that has less importance. (Go to the current Raptor Raid thread if you wanna bug me about my decision >.<, just not here )

The only time I found where the Barracuda severly outperformed the Caviar was in minimum write speed, and I tried googling for info on the differences but couldnt find anything, maybe I suck at searching. Couldnt find anything here on THF either.

Anyway, whats the difference between minimum, average, and maximum write speeds?

Which common computer tasks would fall in which speed type?

I am a digital content creator, and a heavy one at that, meaning I multitask like a motha.

If anyone can answere this question, I would extremly appreciate it since it would influence my decision on whether to spend the extra money or not. THANKS!!!!!

 

[Codesmith]

The speed at which data can be moved to or from a hard drive is highest at the beginning of the drive and lowest at the end.

Hence the maxium, minimum and average.

If you need to ensure the hard drive preforms no slower than X MBps then it needs a minimum write speed above X.

 

[gentrinity]

So in other words, as long as the drive isnt at max capacity, I shouldnt worry about it reaching such low write transfers?

Am i correct, or do I have the beggining and end of HDs mixed up. Does it have to do with the amount of data stored, so when youre at the end your maxing out around the drives limits?

 

[Codesmith]

First part of the drive is fastest. One trick is to partition off the first part of a drive then that section will have a lower minimum write.

To achive full peformance you need to keep the drive mostly empty and deframented, turn off AV software, disc compression and disc indexing.

This is vitally important if you are capturing live high defintion contents and are pushing the limits of your hard drives transfer rates.

If you are not doing live recording then tranfer rates may not be all that important to you.

You might need a drive with the lowest access time and the highest IOps.

Look beyond transferrates and check out the performance database at THG as well as Storage Reivew.

---
Presonally I like the 500 GB RE2's. 5 Year Warranty, Free Advance Replacement.

 

[gentrinity]

Actually, I stated above that those two HDs im looking at are meant to be backup drives. My OS will reside in two raptors in RAID 0.

The minimum write transfer speed of the Caviar worries me a bit, but considering that I probably wont fill up the whole 500GBs any time soon, I guess it shouldnt be such a huge concern. I mean, if I get it over 300GB, ill be amazed. I guess I could always just get the Barracuda as a future upgrade if I find myself reaching the limits of storage. That way, I can have a back up.

 

[pip_seeker]

There are much more to disk drive terms than the ones you mention, however alot of them don't really mean much of anything.

It's more or less a comparison or a group of stats to compare one drive against another. In the real world alot of these stats mean nothing IMO.

It's kinda like you're in the Indy 500 and on paper you have the fastest car. So does this mean you will win the race? Hardly.

You say you are a digital content creator... but give little specifics as to what you actually do. Is it photos, video, music what?

If it's video is it DV, HD Video? you get the idea.

If what you are doing is everything but video then don't worry about it any drive you choose made recently will more than handle the task.

oohing and aahing over every little stat is compeletly over rated and will really mean nothing in terms of real performance.

To put this into perspective a bit further....

Let's say you were capturing DV video. DV captured naitively [meaning that it's not compressed into another format] has a data rate around 3.5MB per second or 13 GB/hr.

A basic 7200 RPM UDMA Drive is capable of Sustained data rates at over 30 MB/s as the drive fills this will drop off but usually you won't suffer any drop frames until you hit close to 90% or more of the size of the disk.

So compared to 3.5MB per sec you have alot of head room for capturing DV video.

Now notice I say "Sustained" data rate. The reason I say that is because that is really the main item you should look for when deciding on a drive or not... all the other stuff really won't matter much.

The reason why sustained is important is because when a drive is written to you want to be sure it can sustain what it is doing, if not performance drops and you'll probably lock up the computer.

Other important factors should be warranty and size of the drive other than that you might look at noise levels, heat etc. But most drives will be pretty comparable in most if not all these areas.

 

[Codesmith]

I think you mentioned backup purposes in your other post not this one.

For file storage purposes any new drive will get the job done and you need not concern yourself with performance, large drive is going to be fast enough.

I like Western Digitals because of their industry leading warranty support. No hassle RMA's, free advanced Replacement option.

Seagate is attractive due to the 5 year warranties on all drives not just thier top ones, but you pay for RMAs either a $27 for advance replacment or $16 fo the special all foam RMA kit they insist you use. Retail packaging is also accepted if you bought retail and kept the box.

PS post some benchmarks on that 2x150 GB Raptor array

 

[gentrinity]

Id love to, but I need to get them first

But if you want benchmarks in the meantime, heres the most thourough ive found yet

http://tweakers.net/reviews/515

The thing about my RAID 0 is that im just splurging at that point cause im already going to start off with 4GB of RAM and plan on moving to 8GB in a few, so basically, my RAID 0 is going to be tainted for the lack of scratch disk and virtual memory. Hey... wait a minute... that means theyll be even faster... just realised that... sweet. God this system is going to kick so much ass. Its too bad im going to have to wait a few more months to get it all complete.

 

[Codesmith]

The problem is that most people expect RAID-0/Raptors to benifit them in ways that it won't or waste money on hard drives that would be best spent on more memory, faster CPU....

You however and seemed to have done your homework. I think you will be pleased with the results.

 

[gentrinity]

Of course, I always try and learn as much as possible, especially when im considering such a big investment.

If youre a gamer, and you ask me about Raptor RAID 0, ill tell you youre nuts. You will see very little benefit, considering that other hardware is alot more important. Now, if you tell me youre a Adobe product user(like me) and the first thing ill tell you is, get more RAM and better CPU, like you said, RAID 0 is the last thing you should look at, UNLESS YOU DO VIDEO EDITING, and not just any video editing, the one thatll see the most benefit is HD editing.

But an interesting thing does occur if youre lookin at price/performance. If you consider 2GB standard for most modern PCs, and you already have a Raptor, Compare the prices;

Adding 2GBs = $300
64bit OS = $140 (im assuming you are legit)
Device drivers non existent = priceless

Additional Raptor = $220

Basically, its a cheaper alternative to get a Raptor in RAID 0 and if you use Adobe products, you will see a decent increase in performance for about half the money. The tweakers.net did find RAID 0 to perform very well in scratch disk scenarios, also having it on dual drives also helps performance, but you would have to study a bit more to find out in which process would benefit from RAID 0 and which ones benefit from two seperate drives. Usually its best to keep the virtual memory and the scratch disks on seperate disks so keep that in mind, so its up to you what actions you think you deem to have a higher priority for performance increase.

HOWEVER

If you multitask like a motha, like me, and will usually have a few Adobe apps running at the same time, as well as a few other diverse apps running, youd be nuts to think that RAID 0 will solve your problems. RAM, RAM, and more RAM. Photoshop alone can take 3GB if you let it. So thats why im considering 8GBs, cause I that way, I wont even need a scratch disks, which is really what you want. Im getting the RAID 0 cause I will get into video editing. But RAM is top priority.

 

[Codesmith]

What bothers me is people subjective claims of faster performance under real world multitasking systems.

Hard to argue when people say it feels faster under conditions that are impossible to reproduce.

What I really would like is for some double blind testing to be done.

Mabye four computers identical except for their hard drive configuration. Ask people at a lan party or computer store to pick which one "feels" the fastest.

I honestly wouldn't be suprised eitherway.

I think my Raptor makes my system feel faster, but I also know that I may be tricking myself.

FYI I did double blind testing to prove to prove to someone that they did not in fact hate mp3s at 128 kbps.

I don't have the time energy or parts to build two identical systems for side by side comparisons. [/list]