What drive configuration in desktop if most data in NAS?

[booq]

Misleading Poll title! Please vote on what drives should go in my "desktop" p182, not in the NAS.
I think I could have phrased that poll title better, and I can't edit it.
Oh to be able to add some more options...or remove the poll...
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So I am building a system here: viewtopic.php?t=49732

I was going to get a Velociraptor, and then get some other drives for RAID 1 storage, but I can't justify the price of it.

So, What will be the best setup in a 182 for me?

Get two WD6400AAKS in software raid 1 and swap out to a NAS later? (looking for low power software NAS solutions, but it's tricky)

Get one WD6400AAKS for / and two notebook drives for /home in RAID 1 and forget the nas?

Some other combination?

The WD6400AAKS is a cheap solution right now, but no telling what serial number I will get. The 750 F1 would be almost $50 more expensive (for two), and I am not sure it would be worth it. WWSPCD? What would you do

Edit: After recommendations against RAID, I'll just work out a backup routine to a NAS, and then make the NAS redundant to an external drive slaved to it. Added poll.

[QuietOC]

Get two WD6400AAKS in software raid 1 and swap out to a NAS later? (looking for low power software NAS solutions, but it's tricky)

Software based RAID 1 could be less reliable than a single drive. Any driver or software error will get written to both drives. Also both drives share the same power supply. I have had a bad drive take out another drive in the same system. The only protection RAID1 offers is if only one drive fails, which is actually a rare event especially with identical drives.

It is more efficient just to periodically back up data to a drive that can be then set on a shelf, or moved to another location. Also replace drives frequently. There is no sense in using drives more than a year old (at least for anything important.)

[booq]

So what should I do instead?

I'll get a NAS (buffalo link station or such) to stay up all the time on the network, and back up to that (and have it back up to an external drive plugged in).

But what will best fit my main system then? One 7200 drive (F1 or 6400AAKS) for root / system, and another drive for /home storage?


(system / ) + (/home data storage)
1x 7200 + 1x 7200
1x 7200 + 1x 5400
1x7200 + 1x 2.5" laptop
1x5400 + 1x 5400
1x5400 + 1x 2.5"
Other?

[Matija]

The only protection RAID1 offers is if only one drive fails, which is actually a rare event especially with identical drives.

On the other hand, I've had two Barracuda IVs in my old computer, RAID-1, and it was only when I've broken the array and left one drive that I found out the second one had a fair share of bad sectors developed over time.

[aztec]

if you haven't gotten the NAS yet...you may want to check out the D-Link DNS-323 or cheaper 321.

The 321 performs just as well, just without the media-streaming and bittorent functions.

[booq]

I really need a small fast / quiet drive for the system, and a quiet "fast enough" drive for /home I think.

Getting two WD6400AAKS or F1 750 drives seems excessive (for the system drive anyway).

Is it? I wish WD would make cheaper smaller versions of the Velociraptor.

[QuietOC]

I wish WD would make cheaper smaller versions of the Velociraptor.

Like 150GB? They do.

There is also a 80GB WD800HLFS OEM version that you can get from Dell.

[booq]

Thanks! I found the 150 on the WD site, but didn't know they were available for sale.

Looking into the 80 GB dells. *Edit, can't find in dell site, I can only find the 300GB

Is it worth it? Are there other fast quiet smaller system drives I should consider? Just don't know if the VR are worth the money. (Although the HDD is always the slowest part of a system)

[QuietOC]

Is it worth it? Are there other fast quiet smaller system drives I should consider? Just don't know if the VR are worth the money. (Although the HDD is always the slowest part of a system)

It is normally more worth it to max out your RAM first.

The WD6400AAKS is a great deal and just slightly noisy. The 150GB VR would be quieter and quicker (as long as you keep it from filling up.)

[booq]

So would you go for 2x wd6400AAKS? Did you vote the 7200 + 2.5" above?

[QuietOC]

So would you go for 2x wd6400AAKS? Did you vote the 7200 + 2.5" above?

I am happy with a single P7K500, which is only faster than the WD GPs. I'd suggest trying a single WD6400AAKS by itself, which wasn't an option, so I didn't vote.

The next step up would probably be a VR (OS/applications) + WD GP (storage) which would probably be as quiet as a single WD6400AAKS.

2 7200rpm drives would be the worst option for noise--you get a high chance of the beat effect with 2 drives that are almost the same speed. I guess a WD6400AAKS + GP would also avoid that--okay, I voted for option 2.

[IsaacKuo]

Unless you have a very good reason to put /home on a different drive, then I'd recommend leaving /home in its default location (on the root partition, along with everything else in the OS).

Clearly, you are thinking of putting the OS on a fast drive for performance. But you seem to not realize how critical /home is for desktop performance. Any software you run as a normal user will be using files in /home. For example, one of the most file intensive desktop applications is a web browser like Firefox--which churns away files in /home like crazy. Similarly, The GiMP or Open Office or...well, just about any normal application you can think of will use /home heavily.

Mostly, it's only server daemons like apache or mysql which hit other directories instead of /home.

The key is to keep /home on the same fast drive as the rest of the OS, and mount any "bulky" data patition somewhere else. For example, you could mount the "big" data partition in /media/sdb5, and put a symlink to it in your home directory.

[Nick Geraedts]

@IssacKuo - Isn't that more of a reason to run two separate drives? You're splitting the IO requests across two disks, which is likely going to be faster than having it all on a single disk anyways.

My personal recommendation would be to buy two quiet 7200RPM drives (WD6400AAKS comes to mind), and mount them like you've suggested - / on the one drive, /home on the other. Again, not a substitute for proper backups, but if your system drive dies it won't take your personal files with it.

@QuietOC - the beat effect would come when the frequencies of the two sources are very close, but significantly apart. A 7200RPM (120Hz) drive mixed with a 5400RPM (90Hz) drive would produce a beat frequency of 30Hz. In other words, you'd hear a beat every two seconds. This is one of the reasons why I moved my entire file server to the WD GP drives - to avoid the 2 second beat. Two 7200RPM drives would have frequencies that are so close together, the beat itself would rarely become aparent.

[booq]

But you seem to not realize how critical /home is for desktop performance. Any software you run as a normal user will be using files in /home. For example, one of the most file intensive desktop applications is a web browser like Firefox--which churns away files in /home like crazy.

Ineed, I am trying to squeeze out more performance. And what you say makes sense - all the user config for programs is in /home. I always separate home to another partition; and was thinking along these lines:

@IssacKuo - Isn't that more of a reason to run two separate drives? You're splitting the IO requests across two disks, which is likely going to be faster than having it all on a single disk anyways.

Thats what I thought.
@Nick Geraedts and @QuietOC - do tell more about the beat frequencies. Nick seems to have a point, I would think that two drives of similar frequencies would create a phasing sound instead of a beat. Great debate![/quote]

[QuietOC]

Two 7200RPM drives would have frequencies that are so close together, the beat itself would rarely become aparent.

A 30Hz beat is not as bad as a ~1Hz beat, which I have experienced with 7,200 rpm drives. The beat shows up as loud -> quiet -> loud etc at ~1 second intervals. The closer the two are together the more pronounced the beat effect is, and the longer the loud part lasts.

[IsaacKuo]

@IssacKuo - Isn't that more of a reason to run two separate drives? You're splitting the IO requests across two disks, which is likely going to be faster than having it all on a single disk anyways.

If your applications hit both disks hard at the same time, and both drives are equally fast, then yes. But with typical desktop use it's more likely to be mostly one or the other. For instance, while web browsing it's going to hit almost entirely /home.

My personal recommendation would be to buy two quiet 7200RPM drives (WD6400AAKS comes to mind), and mount them like you've suggested - / on the one drive, /home on the other. Again, not a substitute for proper backups, but if your system drive dies it won't take your personal files with it.

If I understand it correctly, the basic plan is that a network drive will be used for backups anyway.

@QuietOC - the beat effect would come when the frequencies of the two sources are very close, but significantly apart. A 7200RPM (120Hz) drive mixed with a 5400RPM (90Hz) drive would produce a beat frequency of 30Hz. In other words, you'd hear a beat every two seconds.

This is way off! You are correct that the beat frequency is 30hz. But this isn't one beat every two seconds. It's 30 beats every second. This is so rapid as to be a non-issue.

In contrast, two drives spinning at the same rate is the worst possible for beating. Two 7200rpm drives will not be spinning at exactly the same rate; there is always some beating. This beat frequency may be one beat every few seconds, and to me it's very annoying.

The beating effect is so bad that I actually prefer a file server to have three drives instead of two drives. The beating effect of three identical drives is more complex and sublime; it's the reason why pianos use three strings per note.

This is one of the reasons why I moved my entire file server to the WD GP drives - to avoid the 2 second beat. Two 7200RPM drives would have frequencies that are so close together, the beat itself would rarely become aparent.

This is the opposite of reality. If you don't notice the beating effect of two 7200rpm drives, then it's because you've psychologically convinced yourself to ignore it.

P.S. - I'm sorry. Now that I've corrected you, you'll start noticing the beating effect of twin drives. And it's probably going to start driving you crazy! You can try adding a third drive to transform the horrific beating into a more pleasent grumbling.

[booq]

So one drive? I didn't think that would be the best solution, but it seems like it may be.

It's too bad people scared me so bad about software raid, I didn't want to be tied to a controller, as if the controller failed I could not rebuild until I got another. It seems like that is a lot of hassle. Hence backup to a NAS.

Lots of empy space in the case! At least it'll stay cool...

What are possible criticisms of the single drive?

[lm]

I have the 300GB Velociraptor for Debian and WinXP, and all their programs and data.

sda1 256MB /boot
sda2 84GB /
sda3 16GB swap
sda4 ~200GB winxp

Then I have a WD 640GB for media files. No NAS here.

I'd rather minimize the number of partitions, because it is most convenient. Never have to worry about having space in the wrong partition, and lacking space where it's needed.

The 84GB in the beginning of the Velociraptor contains all of my Debian including home, and I get the benefit of fastest part of the drive, while the windows gets the slower but larger part of the drive, as it's bloated by design and used rarely.

[Nick Geraedts]

Whoops, my math was all wrong there... not sure what I was thinking this morning (hadn't had my coffee yet... ).

I'm not sure where the beating I had came from, but it was definitely my file server with eight 7200RPM drives and two 5400RPM drives. I've got my other system with two WD6400AAKS drives in it (hardmounted - haven't figured out suspension in the Antec 900 yet), and I really can't hear any beats from the system.

[booq]

Overload!

OK, for the first time in years I am rethinking having a separate /home partition. I had always separated it so that I could upgrade / reinstall without messing with my data.

However, based on comments here, I would be better served by having everything on one disk, in one partition, and symlinking to other data on another drive (internal or NAS). As long as the two drives are different RPM, it will avoid the beat problem.

Spend on a Velociraptor and forget extra drives? Get a 7200 and spend the savings on a NAS or another internal drive? I keep bouncing between the options. I need an easy backup solution regardless, as I can't jeopardize my work data.

[IsaacKuo]

Just to confuse you even further, if you really want blazing fast performance, you could RAMboot. The means perhaps investing a bit more in system RAM (more than 2gigs would be nice), and getting your hands a bit dirty with some boot script hacking.

The benefits, though, would be stupendously fast performance and no OS hard drive noise. We're talking about speeds of 3200megs/sec (for DDR2-800) which makes even the fastest SATA SSD look pathetic.

If you really want the best possible speed, max out your RAM, and set up a script to periodically rsync (or rsnapshot) your home directory out to a network drive. Then modify the /etc/init.d/ijkijkijk script to rsync over your home directory from the network drive upon bootup.

I don't have the sort of RAM to pull this off. My main workstation only has 2 gigs of RAM. But with, say, 8gigs of RAM, you could have a healthy amount of "work" data that you would like to process with stupidly fast performance.

[booq]

I read that post! Interesting stuff, didn't recognize you as the author!

This is something that warrants some planning and testing for, I love the concept.

What is your drive setup in linux? (off topic) What do you think would be the easiest way to back up data to a network location? Am I just paranoid to avoid RAID?

[booq]

I read that post! Interesting stuff, didn't recognize you as the author!

This is something that warrants some planning and testing for, I love the concept.

What is your drive setup in linux?

(off topic) What do you think would be the easiest way to back up data to a network location? Am I just paranoid to avoid RAID? Am I best off getting something silly easy like hooking up a DROBO to an wireless router with USB and scheduling backups with Timevault or Rdiff-backup or something? If you have any thoughts on this maybe post in my parent thread or link out to another discussion.

[IsaacKuo]

On my main workstation, there's just a single hard drive. It's partitioned into a small hda1 OS/RAMboot partition and a large hda5 backup data partition. I have a simple script that uses rsync to backup data from my file server to /mnt/hda5.

Basically, I like for the hard drives to be spun down for silence, but I find it perfectly acceptable to spin up the hard drives for a manually run backup. With rsync, only the changed files are copied over, so it doesn't take very long.

Some of my workstations have multiple drives. In all cases, hda1 contains the OS and RAMboot snapstrip.tar image. The hda5 partition and the remaining drives are just backup data. I use a simple script using rsync to backup data from my file server to the backup data drives.

I use aufs to combine hda5, hdb5, and hdd5 into one large file system. Unlike RAID, aufs combines directories on a file system level rather than on a block level. This means that each component partition always remains a perfectly usable ext3 file system regardless of what else is also going on. It's trivial to add or remove partitions from the "array". I can access the component partitions directly to manually move files from one partition to another, if I want to remove/upgrade one of them.

My file server uses a similar configuration. I have the OS in hda1 and I use aufs to combine hda5, hdb5, and hdd5 into a large shared file system. Unfortunately, the out-of-box aufs kernel module in Debian Lenny doesn't support nfs sharing. Rather than compile it myself, I decided to learn how to use sshfs.

[HFat]

Software RAID1 usually works fine if you know what you're doing. The most important thing to understand is that RAID is not a backup solution. Although it can help in some data loss scenarios, the main point of RAID1 is to save you time and effort when a drive fails. Is it worth the cost and trouble? Only you can tell.

Backups over wireless are going to be horribly slow and are likely to interfere with regular usage of the network if you do them often enough as well. Consider using an eSATA enclosure. EDIT: make that two if you care about your data.

Also replace drives frequently. There is no sense in using drives more than a year old (at least for anything important.)

Do you have any data to back this up? Pardon the pun... I would just like to see the evidence.

[lm]

I'm pretty sure that replacing all your drives every year is much more tedious than doing proper regular backups.

And unlike <1year old drives, the backups actually help to keep your data safer. Some drive failures happen to almost new drives.

[twoscoreandfour]

OK, I'm assuming that NAS backup is already a given, and basically you just want your system drives.

If you have two drives of the same speed, there is nothing wrong with having a separate home and separate root partition.

The discrepancy comes if one drive is faster/slower than the other. Thus, if you decide to get two Caviar Blues then it really is a non-issue.

That being said, how much data do you want for your home partition? With 640GB you can use even 600GB for home and still have more than enough to for root. I'm also assuming you don't want to dual boot windows, because that will take a sizeable chunk out of your space. For me 500GB for home suits my needs, but I need windows occasionally, so I've gone with two of the same disks