Best practices for RAID level/performance with separate boot and data drive?

[noobtastic88]

Hello

I have a total of 4 drive bays I need to fill and I need to create an OS volume and a data volume.

I'm struggling with what would be the best approach. I've thought about 2 SSD drives so the OS boots quickly and 2 data drives (each pair in RAID 1). That way I have redundancy.

I've also thought about a PCI boot drive and RAID 10 with 4 data drives.

Do you have any suggestions for what would give me the best redundancy and performance?

thank you

 

[Snipergod87]

I would say just do two RAID 1 array's. Remember that you will have disk redundancy, if you delete a file from the array you do not have a backup.

RAID 10 will give you more performance and increased capacity, if you do this you can always choose to backup a PCI-Express boot drive onto the RAID 10 array.

 

[JackNaylorPE]

I built the box I am typing from with two 256 GB SSDs and two 2 TB SSHDs.

- I did the RAID 0 SSDs to try "one more time" if i could realize and actual performance benefit on the desktop.
- I did the RAID 1 SSHDs for redundancy as this box serves as a CAD workstation, home office server (4 machines), home data and media server (4 machines) my personal gaming box and my son's (pilot) flight sim.

RAID 0 SSDs - As proved true every other time I have built a RAID system, the results again agreed with every review RAID 0 analysis on the desktop. There is no real performance benefit to be gained. Of course if your goal is to get your name oin web site leader boards for storage benchmark performance then go at it .. but if the goal is to actually see an increase in productivity or anything else useful, you will be disappointed. I had hoped to see an advantage in loading / manipulating large CAD / Image files, but such never materialized.

There were problems and Samsung will provide no tech Support on their Pro SSDs because RAID is "not supported". The Samsung utilities will not work when an array is installed. With nothing to be gained and too many headaches to deal with for which i could get no assistance from Samsung, I broke the array. I now have 1 SSD with OS and programs and 2nd SSD has a backup OS and fav games.

RAID 1 SSHDs - here the array worked as designed but was somewhat problematic as 2nd drive would sometimes just disappear. On top of that, problems with the Asus Z87 Maximus Formula board (BIOS Clock Freeeze Bug) made management difficult when it would freeze. To reduce the management overhead, i broke the array and installed Fbackup. The utility backs up the 1st SSHD to the 2nd once daily. I thought about increasing the frequency but our office load just doesnt warrant same, it works flawlessly.

In short I gained no advantage from either array in any observable way wile the management effort was burdensome. As is, the system is more resistant to problems, suffers no performance drop and makes life a lot easier.

The following is a THG post that is over 8 years old ... I have tried RAID 0 three times since then and nothing has changed. I expect however that being so old, some of the links must be dead by now.

========================================

http://en.wikipedia.org/wiki/RAID_0#RAID_0

RAID 0 is useful for setups such as large read-only NFS servers where mounting many disks is time-consuming or impossible and redundancy is irrelevant.

RAID 0 is also used in some gaming systems where performance is desired and data integrity is not very important. However, real-world tests with games have shown that RAID-0 performance gains are minimal, although some desktop applications will benefit.[1][2]

http://www.anandtech.com/printarticle.aspx?i=2101
"We were hoping to see some sort of performance increase in the game loading tests, but the RAID array didn't give us that. While the scores put the RAID-0 array slightly slower than the single drive Raptor II, you should also remember that these scores are timed by hand and thus, we're dealing within normal variations in the "benchmark".

Our Unreal Tournament 2004 test uses the full version of the game and leaves all settings on defaults. After launching the game, we select Instant Action from the menu, choose Assault mode and select the Robot Factory level. The stop watch timer is started right after the Play button is clicked, and stopped when the loading screen disappears. The test is repeated three times with the final score reported being an average of the three. In order to avoid the effects of caching, we reboot between runs. All times are reported in seconds; lower scores, obviously, being better. In Unreal Tournament, we're left with exactly no performance improvement, thanks to RAID-0

If you haven't gotten the hint by now, we'll spell it out for you: there is no place, and no need for a RAID-0 array on a desktop computer. The real world performance increases are negligible at best and the reduction in reliability, thanks to a halving of the mean time between failure, makes RAID-0 far from worth it on the desktop.

Bottom line: RAID-0 arrays will win you just about any benchmark, but they'll deliver virtually nothing more than that for real world desktop performance. That's just the cold hard truth."

http://www.techwarelabs.com/articles/hardware/raid-and-gaming/index_6.shtml
".....we did not see an increase in FPS through its use. Load times for levels and games was significantly reduced utilizing the Raid controller and array. As we stated we do not expect that the majority of gamers are willing to purchase greater than 4 drives and a controller for this kind of setup. While onboard Raid is an option available to many users you should be aware that using onboard Raid will mean the consumption of CPU time for this task and thus a reduction in performance that may actually lead to worse FPS. An add-on controller will always be the best option until they integrate discreet Raid controllers with their own memory into consumer level motherboards."

http://www.hardforum.com/showthread.php?t=1001325
"However, many have tried to justify/overlook those shortcomings by simply saying "It's faster." Anyone who does this is wrong, wasting their money, and buying into hype. Nothing more."

http://jeff-sue.suite101.com/how-raid-storage-improves-performance-a101975
"The real-world performance benefits possible in a single-user PC situation is not a given for most people, because the benefits rely on multiple independent, simultaneous requests. One person running most desktop applications may not see a big payback in performance because they are not written to do asynchronous I/O to disks. Understanding this can help avoid disappointment."

http://www.scs-myung.com/v2/index. [...] om_content
"What about performance? This, we suspect, is the primary reason why so many users doggedly pursue the RAID 0 "holy grail." This inevitably leads to dissapointment by those that notice little or no performance gain.....As stated above, first person shooters rarely benefit from RAID 0.__ Frame rates will almost certainly not improve, as they are determined by your video card and processor above all else. In fact, theoretically your FPS frame rate may decrease, since many low-cost RAID controllers (anything made by Highpoint at the tiem of this writing, and most cards from Promise) implement RAID in software, so the process of splitting and combining data across your drives is done by your CPU, which could better be utilized by your game. That said, the CPU overhead of RAID0 is minimal on high-performance processors."

Even the HD manufacturers limit RAID's advantages to very specific applications and non of them involves gaming:

http://westerndigital.com/en/products/raid/http://westerndigital.com/en/products/raid/

 

[Traciatim]

Personally I would just avoid the RAID setup entirely on your boot and application drive (each an SSD). Just keep your OS on one of the drive and any application that you don't care as much about the performance on, and then the second one houses anything that you want to keep your performance at top speed. As was gone over in the post by JackNaylorPE the RAID SSD does well in benchmarks so it seems fast but then in real world use there is very little noticeable difference except for in a few very special cases.

As for the other two drives for storage I would also suggest that you avoid a RAID and just set up some kind of sync software between the two for data you want access to but have multiple copies on your primary machine. Use an external drive (or online storage) for backups for important data.

The only reason you would choose RAID here would be for if you need a sequential read speed above that of a single drive and want data redundancy on the drive to be immediate when writing (RAID1) or you need a sequential write and read speed faster than a single drive can provide and need extra space but no redundancy on a single volume (RAID0). Otherwise you are just adding complexity and another failure level that you really just don't need at all.

Two separate drives that use syncing software to keep important data on both drives with an offline backup or online backup solution is simple, easy, and works. Plus you get more space available for things that you don't care about losses, which on a storage drive for things like movies, or music, is much better anyway.

This is similar to how I have my current PC set up. I use a single 480GB SSD (for programs/games), a 1TB SSHD (for boot/OS/storage), and a regular 1TB HDD for extra storage and data syncing from the other drives of stuff that I want to keep safe from a drive failure. I also use IDrive for storage of data I want to keep safe (like family photos or stuff that I would really want back if someone stole my PC or a fire destroyed it).

Redundancy is not a backup.

 

[JackNaylorPE]

I also would argue for an external drive. RAID 1 does squat for you when you are trying to replace data on a drive when the PC is stolen or a fire occurs, or maybe even when ya CLC cooler exploded.

I find storage docking stations most useful for this purpose. We make a backup every thursday and remove off site.

http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&DEPA=0&Order=BESTMATCH&Description=blacX&N=-1&isNodeId=1

Also if performance is your goal, I'd strongly suggest SSHDs over HDs. The advantage you get from the SSD is there only for the data on the SSD, all that data on the HDs benefits in now way, shape or form from the SSD.

In the office, we typically wind up working on a set of the same files repeatedly day after day till they gradually get phased out and replaced by new projects. When designing a new bakery for example, as we are now, we open the same CAD files, same spec (word proc) files, same calculations spreadsheets day to day. The SSD recognizes this and moves the frequently used files to the SSD portion of the drive. Over time, as we finish the bakery and move on to next project, those new project files will replace the bakery files.

In gaming it's the same thing .... If I have been playing say far Cry 3, all the FC3 frequently used files are on the SSD portion of the SSHD ... if I move to FC4, then the FC4 files will replace the FC3 ones as the system sees I'm no longer playing FC3.

In fact, since moving to SSHDs 4 years ago, we don't even bother w/ SSDs on laptops and budget (< $1200) desktops. The SSD boots in 15.6 seconds, the SSHD in 16.5 .. we have built two test systems where we can boot / work / play games from either or and no one noticed the difference. Still ... if ya have the budget, with prices as they are now, we'll put in SSDs from more of a "why not" standpoint as a "why". Our three platforms now include:

SSHD
SSD + SSHD
Multiple SSDs and / or SSHDs

If you are the type of gamer who plays 8 different games on Tuesday and then again a different set of 6 on Friday, the SSHD is not going to help you all that much.